Old Fashioned Rhubarb Pie Recipe

Get ready to enjoy the perfect mix of sweet and tart with this old-fashioned Rhubarb Custard Pie. The creamy custard pairs so well with tangy rhubarb, creating a rustic yet elegant dessert that’s surprisingly easy to whip up. This recipe has been handed down from my mom and has been a beloved family treat for years—I’m sure it’ll be a new favorite in your home, too.

Rhubarb custard pie is a timeless dessert that marries the tangy bite of rhubarb with the silken sweetness of custard. Usually, this means a flaky crust loaded with fresh, diced rhubarb and a rich custard made from eggs, sugar, milk or cream, plus a bit of flour or cornstarch to help it set. The tang from the rhubarb and the smooth sweetness from the custard strike the perfect flavor balance in every forkful. It’s a must-make during spring and early summer when rhubarb is at its prime and freshest.

Actually, it’s so good that my mom grew her own rhubarb just to bake this pie, and hers has no strawberries—just creamy, lightly sweet custard mixed with tart rhubarb that tastes a little like green apples. She also bumped up the flavor by adding nutmeg, which gives the pie a warm, cozy touch. All those flavors come together beautifully!

Hi there! Here’s my mom’s beloved old‑fashioned Rhubarb Custard Pie—a straightforward, heartwarming springtime dessert where tart rhubarb is nestled into smooth, eggy custard and a flaky pie crust. Baking this pie fills your kitchen with that cozy “home” aroma. It’s easy enough for a weekend treat but fancy enough to serve to guests without stress.

Down below, you’ll find a complete ingredient list (mostly pantry staples), clear step‑by‑step instructions to assemble and bake it, plus tips for getting a perfect crust and a pretty lattice top. I also share some cool variations (like adding strawberries or using a richer custard), plus advice on storing, reheating, and answers to common rhubarb questions.

• Total time: about 1 hour (roughly 20 minutes prep and 40 minutes baking)
• Makes one 9‑inch pie, serving about 8 hungry folks
• Skill level: super approachable—my detailed steps walk you through every part, perfect for beginner bakers

Keep reading for all the details—whether you’re using fresh garden rhubarb or picked up a bunch at the store, this classic pie is a wonderful way to enjoy spring.

What Makes This Pie Special

Here’s why you’re going to adore this Rhubarb Custard Pie:

1. Sweet and tangy magic. The smooth custard gently offsets the rhubarb’s tart zing. If you prefer the classic berry pairing, try our Strawberry Rhubarb Pie for a brighter, fruit-forward take.
2. Simple to pull off. Even if you haven’t made pie before, my easy-to-follow directions make it a breeze to bake something delicious and impressive. And hey, the lattice top is totally optional if you want to keep it simpler! If you’re new to working with the stalks, this guide to preparing, storing, and freezing rhubarb can help.
3. Classic, comforting flavor. Rhubarb custard pie has stood the test of time, and this recipe keeps that cozy, nostalgic vibe alive and well—similar to a traditional Rhubarb Custard Kuchen.
4. Great for any occasion. Whether it’s a family dinner, holiday gathering, or just a well-deserved treat for yourself, this pie fits right in. For a potluck-friendly twist, a rustic Rhubarb Tart with Oat Crust travels beautifully, too.
5. Tastes great warm or cold. I love it warm with a scoop of vanilla ice cream, but it’s just as lovely chilled on a sunny afternoon.

Gather Your Ingredients

• Prepared pie crusts (top and bottom, 9-inch)
• 3 large eggs
• 1 egg (for egg wash) beaten with 1 tablespoon water
• Whole milk
• Melted butter
• Fresh rhubarb stalks, peeled and chopped
• Granulated sugar
• 4 tablespoons all-purpose flour (I like unbleached and organic for the best flavor and texture)
• Ground nutmeg

Assemble and Bake the Pie

1. Trim off and discard rhubarb leaves, peel away any stringy bits, and chop the stalks into pieces.
2. If rhubarb is limp, soak stalks in cold water for about 1 hour to crisp them.
3. Heat the oven to 400°F (200°C).

4. Prepare pie crusts: fit the bottom crust into a 9-inch pie pan and prepare a top crust or lattice.

   
5. Whisk together 3 large eggs, the milk, and melted butter in a small bowl; set aside.
6. In a large bowl, stir together the chopped rhubarb, granulated sugar, all-purpose flour, and ground nutmeg.
7. Pour the egg-milk-butter mixture into the rhubarb mixture and stir until evenly combined.

8. Spread the rhubarb-custard filling evenly into the prepared bottom crust.

   

9. Place the woven lattice or top crust over the filling and seal/crimp the edges.
10. Beat 1 egg with 1 tablespoon water and brush the mixture over the top crust.
11. Bake the pie at 400°F for about 40 minutes, or until the filling is set and the top is golden brown.

12. If the crust edges brown too quickly, cover them with a pie crust shield or aluminum foil while baking.

    

13. Remove the pie from the oven and let it rest at room temperature for about 10 minutes before slicing.

    

Serving Ideas and Pro Tips

This pie is fantastic served warm or at room temperature. My favorite way is with a big scoop of vanilla or caramel ice cream melting on top—it just takes it to the next level! For an extra fruity finish, add a spoonful of strawberry rhubarb jam. Prefer a sweeter, cookie-like base? Next time, try baking it in a graham cracker crust.

Flavor Twists and Substitutions

If you want to switch things up but keep that classic rhubarb-custard feel, try one of these fun tweaks:

• Strawberry-rhubarb twist: Add 2 cups of sliced, hulled strawberries to the rhubarb and reduce the sugar by 1/4 cup for a sweeter, fruitier taste. (Mom skipped strawberries in her pie, but this combo is so popular.)
• Extra creamy custard: Swap the whole milk for half-and-half or heavy cream in the same amount to make the filling richer and velvetier.
• Glossy, set filling: Instead of 4 tablespoons of flour, use 2 tablespoons of cornstarch mixed with the sugar before adding the fruit. You’ll get a firmer, shinier custard.
• Spice it differently: Swap or add 1/2 teaspoon cinnamon or 1/4 teaspoon cardamom with the nutmeg for a warm, cozy flavor kick.
• Sugar swap: Use half granulated sugar and half light brown sugar for a subtle caramel note, or reduce the sugar a bit if your rhubarb is less tart.
• Crust changes: Skip the lattice and cover with a solid crust with vents, try a crumb or streusel topping inspired by a classic British rhubarb crumble, or grab a store-bought crust to save time. Gluten-free crusts work well too with the same amounts.
• Mini versions: Divide filling into muffin tins or mini tart pans for single servings. Keep an eye on them and bake 20-30 minutes until the custard sets.
• Custard firmness: Use all 4 eggs for a firmer set, or stick to 3 eggs as the recipe says for a softer custard that still holds up beautifully.

Cooling, Storing, and Reheating

Once your pie has cooled completely, cover it tightly with plastic wrap or aluminum foil—make sure the edges of the crust are well covered so they don’t dry out. Keep your pie in the fridge for up to 3 days.

I don’t recommend freezing this pie because custard can get watery and separate when thawed, and nobody wants a soggy custard pie. If you want a rhubarb dessert that’s great when you only have frozen fruit on hand, try this Classic Rhubarb Crisp with Frozen Rhubarb.

If you have leftovers, wrap each slice individually with plastic or foil and store them in the fridge, where they’ll keep well for up to 3 days.

To warm it up, lightly cover the pie with foil and bake in a 350°F oven for 10-15 minutes until heated through. Be careful not to heat it too long or the custard might loosen too much. Let it cool a bit before digging in. Keep in mind reheating might soften the crust’s crispness a bit compared to freshly baked.

Rhubarb Custard Pie FAQs

What does rhubarb taste like?

Rhubarb tastes bright and tart, kind of like green apples with a little lemon zest mixed in. If you enjoy that lemony tang in a quick bread, try this Lemon Rhubarb Loaf.

How do you prepare rhubarb for pie?

Make sure to peel away any stringy parts and remove all the leaves—they’re toxic! If your rhubarb looks a bit limp, popping the stalks into cold water for an hour can help freshen them.

Do I need to cook rhubarb before making the pie?

Nope! The rhubarb softens and cooks right in the pie with the custard, so no pre-cooking needed. By contrast, some fruit pies use a pre-cooked filling—see our homemade cherry pie filling for an example.

Can I make this rhubarb pie ahead of time?

Absolutely! You can prepare the pie crust ahead and brush the inside with a beaten egg and water mixture before adding the filling. This helps keep the crust from getting soggy when baked the next day.

Common Questions About Rhubarb Pie

What does rhubarb taste like?

Rhubarb tastes bright and tart, kind of like green apples with a little lemon zest mixed in.

How do you prepare rhubarb for pie?

Make sure to peel away any stringy parts and remove all the leaves—they’re toxic! If your rhubarb looks a bit limp, popping the stalks into cold water for an hour can help freshen them.

Do I need to cook rhubarb before making the pie?

Nope! The rhubarb softens and cooks right in the pie with the custard, so no pre-cooking needed.

Can I make this rhubarb pie ahead of time?

Absolutely! You can prepare the pie crust ahead and brush the inside with a beaten egg and water mixture before adding the filling. This helps keep the crust from getting soggy when baked the next day.