Rhubarb Pie Recipe

Grandma’s Secret Rhubarb Pie Recipe – The Magic Ingredient? Tapioca!

There’s something truly magical about a homemade pie. The flaky crust, the sweet-tart filling, and the comforting aroma that fills the kitchen make baking an experience like no other. One of my fondest memories is baking rhubarb pie with my grandma, who had a special trick up her sleeve. Her secret? Tapioca!

If you’ve ever struggled with runny rhubarb pie filling, you’re not alone. But today, I’m sharing the best rhubarb pie recipe using tapioca, so you can create a thick, luscious filling that holds together beautifully. Whether you’re using fresh or frozen rhubarb, this pie will be your new go-to dessert, perfect for summer gatherings or even Memorial Day desserts. Let’s dive in!

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Why Tapioca is the Secret to the Best Rhubarb Pie

Rhubarb naturally releases a lot of liquid when baked, which can make pies runny and soggy. Many recipes use cornstarch or flour as thickeners, but Grandma swore by quick-cooking tapioca. Why?

Tapioca absorbs excess moisture without making the filling cloudy.

It creates a perfect, jelly-like consistency.

The filling remains vibrant and smooth, never gummy.

Once you try this method, you’ll never go back to flour or cornstarch!

Ingredients for Grandma’s Rhubarb Pie

For the Filling:

4 cups rhubarb, chopped (fresh or frozen rhubarb thawed and drained)

1 1/4 cups granulated sugar

1/4 teaspoon salt

3 tablespoons quick-cooking tapioca

1 teaspoon vanilla extract

1 tablespoon lemon juice

1/2 teaspoon cinnamon (optional, but adds warmth)

1 tablespoon unsalted butter, cut into small pieces

For the Pie Crust:

2 1/2 cups all-purpose flour

1 teaspoon salt

1 tablespoon granulated sugar

1 cup (2 sticks) unsalted butter, chilled and cubed

6-8 tablespoons ice water

1 egg (for egg wash, optional)

Step-by-Step: How to Make This Easy Rhubarb Pie Recipe

1. Prepare the Rhubarb Filling

If using frozen rhubarb, thaw and drain it well to remove excess liquid. In a large mixing bowl, combine the rhubarb, sugar, salt, tapioca, vanilla extract, lemon juice, and cinnamon. Let it sit for 15-20 minutes so the tapioca can start absorbing the moisture.

2. Make the Pie Crust

In a food processor (or by hand), mix flour, salt, and sugar. Add butter and pulse until the mixture resembles coarse crumbs. Slowly add ice water, one tablespoon at a time, until the dough comes together. Divide into two disks, wrap in plastic, and chill for 30 minutes.

3. Assemble the Pie

Roll out one dough disk and fit it into a 9-inch pie dish. Pour the rhubarb filling into the crust and dot with butter. Roll out the second disk, place over the filling, and crimp the edges. Cut slits on top for steam to escape. Brush with egg wash for a golden finish.

4. Bake the Pie

Preheat your oven to 375°F (190°C). Bake for 45-50 minutes until the crust is golden and the filling is bubbling. Let it cool for at least 2 hours before slicing to allow the filling to set.

Top Kitchen Tools for Perfect Rhubarb Pie

Making pie from scratch is so much easier with the right tools! Here are three must-haves from Amazon to elevate your baking experience.

1. Pyrex Glass Mixing Bowl Set

I always recommend Pyrex Glass Mixing Bowls because they’re durable, microwave-safe, and perfect for mixing pie fillings. The clear glass lets you see how well your ingredients are incorporated, and they come in multiple sizes for all your baking needs.

Get yours here: Pyrex Mixing Bowls on Amazon

2. Adjustable Rolling Pin with Thickness Rings

For an evenly rolled pie crust, the Adjustable Rolling Pin is a lifesaver! It comes with removable rings to ensure a uniform thickness, preventing uneven baking.

Grab this rolling pin here: Adjustable Rolling Pin on Amazon

3. USA Pan 9-Inch Pie Pan

For a perfectly baked pie, I highly recommend the USA Pan 9-Inch Pie Pan. It’s non-stick, durable, and provides even heat distribution for a golden crust.

Order yours now: USA Pan Pie Pan on Amazon

Tips & Tricks for the Perfect Rhubarb Pie

1. How Long to Let Tapioca Sit Before Baking?

Letting the filling sit for at least 15 minutes allows the tapioca to start absorbing excess liquid, which prevents a watery pie.

2. Can You Freeze Rhubarb Pie?

Absolutely! Here’s how:

Before Baking: Assemble the pie, wrap it tightly in plastic wrap and foil, and freeze for up to 3 months. Bake directly from frozen at 375°F, adding an extra 15-20 minutes to the baking time.

After Baking: Let the pie cool completely, then wrap it well and freeze for up to 2 months. Thaw overnight in the fridge and warm in a 325°F oven before serving.

3. Best Ways to Serve Rhubarb Pie

Warm with a scoop of vanilla ice cream

Topped with fresh whipped cream

Dusting of powdered sugar for a simple touch

Why This Recipe is Perfect for Memorial Day & Summer Gatherings

There’s nothing like a homemade pie to bring family and friends together, and this easy rhubarb pie recipe using tapioca is perfect for Memorial Day desserts. It’s bright, fruity, and nostalgic—just the way summer should taste! Plus, you can make it ahead of time, freeing you up to enjoy the holiday with loved ones.

Final Thoughts

Now that you have Grandma’s best rhubarb pie recipe using tapioca, it’s time to bake your own! Whether you’re making it for a holiday, a weekend treat, or just because—this pie is bound to impress.

If you try this recipe, I’d love to hear how it turns out! Drop a comment below or tag me on social media with your pie photos. And don’t forget to grab the best kitchen tools from Amazon to make baking easier.

Happy baking!