Rhubarb Dump Cakern

Name: Rhubarb Dump Cake
Prep time: 5 min
Cook time: 45 min
Total time: 50 min
Ingredients: 4 cups fresh rhubarb, ((1 to 1¼ pounds) small diced); 1½ cups granulated sugar; 2 tablespoons cornstarch; 1 teaspoon vanilla extract; 1 cup water, (divided); 15.25 ounces yellow cake mix (super moist, (I used Betty Crocker)); 1 cup unsalted butter (melted)

a close up shot of a piece of Rhubarb Dump Cake on a plate

This rhubarb dump cake is the perfect combination of tart and sweet baked to bubbling, and will be a winner whether you serve it for a special occasion or every day treat.

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Table of Contents

Rhubarb Dump Cake Ingredients
How to Make This Rhubarb Dump Cake Recipe
How To Serve
Storage
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This rhubarb dump cake is ridiculously easy to make, and it’s a great way to use up any leftover rhubarb you might have. Imagine digging into this warm, bubbling buttery dish featuring tart rhubarb and a sweet cake topping.

Rhubarb Dump Cake Ingredients

Rhubarb Dump Cake raw ingredients that are labeled

NOTE: It is essential to ensure that you do not eat the leaves, root, or bottom stem area of rhubarb, as it will make you sick.

You’ll need:

4 cups (1-1¼ pounds) fresh rhubarb, small diced
1½ cups granulated sugar
2 tablespoons cornstarch
1 teaspoon vanilla extract
1 cup water, divided
1 (15.25-ounce) box yellow cake mix (I used Betty Crocker)
1 cup unsalted butter, melted

PRO TIP:

When buying the cake mix at the grocery store, it is best to pick one that doesn’t have pudding mix in it; check the label to make sure.

SUBSTITUTIONS AND ADDITIONS

RHUBARB: If you can not find fresh rhubarb in your local market, many grocery stores will carry it in the frozen fruit section. Dole is a very popular brand.

How to Make This Rhubarb Dump Cake Recipe

OUR RECIPE DEVELOPER SAYS

You’ll want to use a 9×13-inch cake pan so that the texture and consistency are right. I’ve used an 11x 7-inch pan before, and it turned out a little too thick, which changed the delicious texture of the dump cake.

STEP ONE: Preheat the oven to 375°F. Spray a 9×13 pan with baking spray. Set aside.

PRO TIP:

Rhubarb does need to be peeled or prepared beyond rinsing and cutting off the ends of the stalks. Do not consume any rhubarb leaves as they are toxic.

STEP TWO: Combine the diced rhubarb, white sugar, ½ cup water, cornstarch, and vanilla extract in a large bowl. Stir to combine evenly. Pour the fruit mixture into the bottom of the baking dish.

PRO TIP:

Fresh rhubarb can sometimes have strings similar to celery that you can just pull off with a sharp paring knife. Usually, it is the larger stalks that have more strings. The smaller, more tender stalks can easily be sliced or diced without removing them.

rhubarb, sugar, water, cornstarch and vanilla stir in a bowl

STEP THREE: Evenly sprinkle the box of cake mix over the top of the rhubarb mixture. If needed, you can spread the cake mix to ensure that all the fruit is covered in an even layer.

cake mix sprinkled on top of the rhubarb mixture

STEP FOUR: Drizzle the remaining ½ cup of water evenly over top of the dry cake mix.

STEP FIVE: Carefully drizzle the melted butter evenly over the water and yellow cake mix.

melted butter drizzled over the water and yellow cake mix

STEP SIX: Bake for 45 minutes or until golden brown and bubbly. Remove the rhubarb dump cake from the oven and allow it to rest on the counter for 15 minutes before serving.

PRO TIP:

Oven temperatures vary and may need to be recalibrated periodically to ensure they are accurate. Make sure to keep a close eye on your rhubarb cake as the suggested baking time approaches.

How To Serve

This easy dessert tastes fantastic and would be a great option to serve when company is coming for dinner. Add a scoop of vanilla ice cream and whipped cream to the plate and everyone will love the warm, bubbly deliciousness.

Dump cakes are always a winner for a quick dessert, and while they may not look pretty, they are beyond delicious. Don’t forget to try our lemon dump cake and strawberry dump cake too.

MORE CAKE RECIPES

Dump Cakes

Chocolate Dump Cake

Dump Cakes

Blueberry Dump Cake

Storage

IN THE FRIDGE: This rhubarb dump cake should be served warm. It can be stored in the refrigerator for 3 to 4 days in a covered container. You can reheat individual servings in the microwave for 30 seconds.

IN THE FREEZER: Store this dump cake in an airtight container for up to 1 month in the freezer. Let it thaw in the fridge overnight when you are ready to serve it.

overhead shot of Rhubarb Dump Cake with a spoon on a baking dish

This easy rhubarb dump cake creates an amazing dessert in only a few minutes of prep time. With the tart and tangy freshness of rhubarb that just screams spring, you will have a new favorite dessert to add to your recipe box.

FREQUENTLY ASKED QUESTIONS

Where can I get fresh rhubarb?

You can often find rhubarb at the farmers’ market during rhubarb season, and if you are lucky, you can sometimes find it at the grocery store as well.

Is rhubarb poisonous?

The stems, roots, and leaves of a rhubarb plant are poisonous because of their high oxalic acid content. The rhubarb stalks, however, are not and can be eaten safely.

Can I use a white cake mix instead of yellow?

You can substitute white cake mix for yellow cake mix in this simple recipe.

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