All the deliciousness of a creamy rhubarb custard pie without any crust-fussing. This simple blender recipe forms its own crust on the bottom, with a delicate custard layer in the middle and a tangy rhubarb layer on top . . . and it only takes 10 minutes to get this pie into the oven! (The gluten-free version works wonderfully, too.)
It's kitchen magic! You pop a few ingredients into the blender, pour it over a pie pan filled with sliced rhubarb, bake it, and voilà, you've got an amazing custard pie. There are three glorious layers - a slightly firmer bottom layer, a middle layer of creamy, silky vanilla custard sweetened with a delicate whiff of nutmeg, and a lot of tangy, fruity rhubarb rubbling the top with its glorious pinkness. This is my kinda pie, and will quickly become yours, too, for those times when you want to impress but have no time.
Who remembers being a kid and walking barefoot around the yard, holding a little cup of sugar in one hand and a big stalk of rhubarb in the other? Dipping the rhubarb into the sugar and crunching on the juicy stalk while your cheeks puckered and your eyes crossed from the intense sourness was one of childhood's summer pleasures. We'd dare each other to see who could eat it while keeping a straight face! Now you can enjoy that same delightful taste sensation in a piece of pie - and it's a lot less pucker-inducing. In fact, it's absolutely, sweetly delicious.
The Rhubarb is Growing - Come Look at the Garden
We had a short, delayed spring, but somehow over the last two weeks it became summer! It's been cloudy and cool, and winter seemed to drag on forever. We got into the garden late this year, squeezing the seeding in between rainy spells. But as usual, with our long northern days of extended sunlight hours, everything popped up somehow (along with the weeds) and suddenly we're gardening again!
The rhubarb plants have become monsters almost overnight. The giant variety we have gets to about 5 feet tall (1.5 metres) every year. I've already removed an armful of flowering stalks from it. The regular variety, in front of the giant plant in the photo below, has redder stalks, and that's the one I use for pie. The giant variety is amazing for juice and cordial, its thick stalks are crisp and juicy. You can see we've started a new row of smaller rhubarb plants to the left of the mature rhubarb. Once the new row is established, we'll remove the big old plants so we have more space between the rhubarb and the new rows of raspberries we've started in our orchard garden.
Two weeks ago we planted most of our vegetable garden. My mom was an energetic helper - she's 85 years young, and I can hardly keep up with her!

In the last few years deer have become a persistent problem in our garden - those pesky unwanted guests would regularly come and greedily help themselves to whatever delicacies they liked from our garden buffet. It was infuriating! I'd wake up every morning to go look at the garden with dread, wondering which rows they'd destroyed the night before. We had tried everything - covering the rows with tunnels of stucco wire (they ate through the holes). Hanging bars of scented soaps from poles every few feet around the perimeter of the garden (they seemed to love the smell), sprinkling a border of shaved soap around the outside of the garden (ditto), sprinkling blood meal and hair clippings everywhere (no luck, the deer just seemed to thumb their noses at our foolishness). So last year we put up a fence of fine-meshed deer netting about 5 feet tall - they still jumped over it! It wasn't until we added an extension of a string that was one foot higher (total of 6 feet/2 metres high) that they finally gave up, moved on, and found a new restaurant to frequent. You can see the new extension with the pink flagging hanging from it - just want to make sure the deer can see it and decide to stay out for good! We're sticking with the temporary fence for now, so that we can take it down every winter and our friend Ed can come in with his tractor to till the garden.


The herb bed along the south side of the greenhouse is lush and glorious already - the chives, garlic chives, tarragon, oregano, sorrel, and thyme come back every year. Sage lasts for 2 to 3 years, then dies out. I tuck annual herbs between the perennial ones every year - rosemary, lemon balm, marjoram, savory. Lovage has a permanent spot in the peony border. Chervil, mint, and camomile are in the pots to the left in the photo. In the garden, dill, cilantro, and borage self-seed all over the place and I leave them where they like to grow (though I only let a couple of borage plants stay), plus I seed parsley, basil, and purslane in the rows.

Last year I planted red orach from seeds given by a Swiss friend of mine. The plants grew as tall as me and I couldn't keep up with them. They seeded all over the place and now they're homesteading in our asparagus patch! This year I've been more intentional about using them - orach is a wonderful delicate heritage green that can be used just like spinach, both raw and cooked. Their purple leaves turn green once cooked. Very tasty! I'm planning to keep the plants under control this year, and am very happy with them as an addition to our garden. I've read that if you keep them pinched, they will be prolific providers of greens all season long!

The strawberry patch is looking promising - can hardly wait for the berries!

This is our garden now, two weeks later. We've started adding grass clippings for mulch along the pathways, the pea fence is up, the broccoli, cauliflower, and kale are thriving under their tunnels of shade cloth (to keep out those white butterlfies that turn into little green worms later on), and the weeds are coming up as quickly as the plants! I'll get out there to hoe them if these nightly rains finally stop. We've had lots of good moisture lately.

The chickens are happily scratching away in their coop. I know they'd like to be checking out the garden, but we have visits from neighbourhood dogs, so they're safer in their pen.
Back to the Amazing Crustless Rhubarb Custard Pie
Pink rhubarb makes the most pretty pie, but even if your rhubarb is mostly green in colour, the flavour will be just as fantastic.
Once you have the rhubarb thinly sliced (thinner slices cook faster and spread out more evenly while baking), just pile it into a generously buttered pie pan. Then whiz up the custard ingredients in a blender and pour the liquid batter over the rhubarb. Tap any sticking-up pieces of rhubarb with a spoon so they are submerged and get coated with the batter. Then bake.
This rhubarb custard pie is part of the 'Impossible Pie' family - that magical confection that doesn't need a crust. While it's baking, the batter magically separates into three distinct layers. The flour sinks to the bottom to make a thicker, slightly firmer crust, and the center becomes a beautiful custard, lightly sweet and delicately creamy. Meanwhile, the rhubarb floats to the top to form a pink and nubbly layer of that characteristic rhubarb tanginess - the quintessential flavour of spring's first offering.

Rhubarb Custard Pie - Gluten Free?
Yes, this pie works equally well with gluten free flour. In fact, the one in the photo above was made with it. After some (delicious) testing, I found that a combination of half gluten free flour blend and half regular white rice flour produces the same results as with all-purpose flour. I tried it with all rice flour - bottom crust was too thick and heavy - and with all gluten free flour blend - great results, lovely custard, but no bottom crust layer. (So the recipe does also work great using all gluten free flour blend - it slices beautifully, but you just won't have a thicker bottom layer, which isn't really a problem.)
In less than 10 minutes you can have this pie in the oven. Who doesn't want that as summer comes on? More time to enjoy the sunshine and maybe pull a few weeds!
Looking for More Delicious Rhubarb Recipes?
- Mom's Rhubarb Cake
- Rhubarb Cordial, Two Ways
- Rhubarb Curd
- Rhubarb and Spruce Tip Galette
- Honey Rhubarb Ice Cream
- Rhubarb Crisp
- Strawberry Rhubarb Pavlova Cake
- Eton Mess with Saskatoons and Rhubarb
- Baked Rhubarb Compote with Swedish Cream
- Rhubarb Gin Kombucha Cocktail
Guten Appetit!
* * * * *

Crustless Rhubarb Custard Pie
Equipment
- 1 pie pan, 9-inch (23cm) deep-dish or 10-inch (25.5cm) - or use an 8 or 9-inch square baking dish.
- blender or immersion blender
Ingredients
- ½ cup (115gms) soft butter, salted divided
- 3 cups (375g) thinly sliced rhubarb (¼-inch/.5cm slices)
- 4 large eggs
- 1 cup (240ml) milk
- ¾ cup (150gms) sugar preferably natural evaporated cane sugar
- ½ cup (70gms) flour [for gluten-free, use ¼ cup (30gms) gluten-free flour blend + ¼ cup (40gms) white rice flour, or use all gluten-free flour blend]
- 1 teaspoon pure vanilla extract
- ¼ teaspoon ground nutmeg optional
Instructions
- Preheat oven to 350°F (180°C).
- Use 1 tablespoon of the butter to generously grease the pie pan. Melt the rest of the butter and allow it to cool slightly before adding it to the batter.
- Thinly slice the rhubarb stalks (¼-inch/.5cm slices) and spread them evenly into the buttered pie pan.
- Put the eggs, milk, sugar, flour, vanilla, and nutmeg into a blender canister. Add the slightly cooled melted butter. Blend for 1 to 2 minutes until smooth.
- Pour the batter over the rhubarb in the pie pan. Push down any floating pieces of rhubarb so they are coated with batter.
- Bake for 45 to 50 minutes, until the top is nicely browned and evenly puffed up.
- Allow the pie to cool completely before cutting into 6 (or 8) wedges. Serve at room temperature or chilled, with ice cream or softly whipped cream.
- The pie will keep, covered, in the refrigerator for 3 to 4 days (if it lasts that long).
Notes
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Merry
Would using rhubarb and strawberries work with this recipe?
Margaret
Yes, I think they should work fine. Since strawberries are a little less juicy than rhubarb, the pie might be a little firmer, which should still be fine. I bet it'll taste great! I think I may have to try that this summer. 😋
Paula
It needed more sugar. Called for 3/4 cup of sugar & I put in almost one cup. It was very tart still. We used whipped cream on it so helped to sweeten it. Good recipe just not sweet enough.
Margaret
It's great you adjusted the sugar to your tastes - that's the beauty of recipes and how you can make them your own. We like the tartness, so the lesser amount of sugar works for us, but everyone can adjust the recipe to their prefered level of sweetness.
Jane
Very tasty pie. I added 1/2 tsp of nutmeg. I love rhubarb. Thus recipe is a keeper.
Margaret
Aw, thanks very much! 😍 I love nutmeg, too - it complements custard desserts so well!
Erika
Do you use fan assisted oven or regular (in German Umluft oder Ober- Unterhitze)?
I guess normal, as you are preheating the oven and we want the bottom to firm up.
Greetings from Germany!
Margaret
So nice to hear from you in beautiful Germany! Yes, I use a regular oven, no fan assist.
Ich wünsche dir viel Spaß in der Küche! 🧡
Gidget Duz
Can one use frozen rhubarb that has been thawed?
Margaret
Yes, that should work but it would keep the liquid ratio better if you used the rhubarb while it's still frozen, as long as it's been frozen on a cookie sheet and the pieces are separate. If the rhubarb pieces have been frozen in a clump, then you'd have to defrost it first and drain it, and I'd use a bit more milk to replace the liquid in the recipe.
Susanne Ledbetter
Can I use frozen rhubarb?
Margaret
Hi Susanne - I haven't made it with frozen rhubarb, but I'm sure you could. I'd stir the rhubarb pieces in while they're still frozen, so that they release their juices just like if they were fresh.
Karen Cory
Love this pie! It is really good. Liked that the recipe calls for things I normally have in my pantry and fridge. So easy to make. This is a keeper.
Margaret
I'm so glad you love it! It really is a great basic pie and easy to make any time. To me it is the taste of summer! Thanks for stopping by to comment.
Happy Baking!😍
Elizabeth Johnson
Can you use any fruit? I have an over abundance of peaches at the moment.
Margaret
Hi Elizabeth, yes this pie will work with other fruit, but I'd increase the amount of milk, depending on how juicy your fruit is. When I make it with coconut (that was my mother-in-law's original recipe) I use 2 cups of milk, but I found I needed to keep decreasing the amount of milk when I used rhubarb, because it was so juicy, and finally landed on 1 cup as the right amount. With peaches, I'd try for about 1 and 1/4 or 1 and 1/2 cups of milk, depending on how juicy they are. Happy Baking! ❤️
Marie
Would this recipe work with blueberries? If so I have frozen blueberries. Would that work or would fresh be best?
Margaret
Yes, it should work fine with blueberries. I'd use the frozen ones without defrosting them first, just toss them in (with any clumped-together ones separated).
Sher
Can cashew milk be substituted for cows milk?
Margaret
Yes, cashew milk would work great in this recipe.
Margot van Lindenberg
This recipe is basically an adapted copy from the Coconut custard recipe in the "More withe Less" older cookbook . and, it is not too sweet. That is a basic custard recipe. Many people are simply getting addicted to sugar.
Margaret
You're right about the sugar thing - it's pervasive in our society now, and scary how addictive it is. I've adapted the Coconut Custard Pie recipe from an old Canadian Kinette Cookery book published some time in the late '70s or early '80s, so I think the recipe has been around for a long time already. I did cut the sugar down a lot and had to reduce the milk a lot as rhubarb is so juicy. It took a lot of (delicious) practice versions til I got it how we like it now.
Molly
This recipe is wonderful! I used two cups of rhubarb and one cup of blueberries. Everything set up beautifully and the sweet/sour ratio was perfect.
Margaret
Awesome! Thanks for the feedback. Rhubarb and blueberries are the taste of summer!
Carol
Do you think almond flour would work?
Margaret
I haven't tried it so I can't say. Almond flour wouldn't be as absorbent, so I would combine it with some kind of starch, like cornstarch or potato starch. I'd try either half almond flour and half starch, or maybe up to 2/3 almond flour and 1/3 starch. If you try it, I'd love to hear how it works. Happy Baking!