Rhubarb Dump Cake Recipe {without Jello}

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For all the rhubarb lovers out there; this rhubarb dump cake recipe is made without Jello for a tiny bit healthier and oh so delicious dump cake recipe. Use fresh or frozen rhubarb, your choice, it is an easy dessert you will make over and over again.

Raise your hand if you love rhubarb? Mine is raised high; I adore rhubarb recipes, there are so many great ways to use this versatile, tart and tangy spring to summer vegetable — yes, vegetable, more on that later. And if you have tons of rhubarb then you are going to love this recipe.

We love rhubarb around here, as do my readers, try my popular old-fashioned rhubarb bread, Strawberry Rhubarb Salad, Best Strawberry Rhubarb Crumb Bars or this simple rhubarb cake.

Rhubarb 101

What is Rhubarb?

Even our country struggles with whether or not rhubarb is a vegetable or a fruit.

Fun Fact: While rhubarb is technically a vegetable, the USDA classifies it as a fruit. Read more about this below.

The perennial Rhubarb plant has a pretty short season for a vegetable, abundant in the spring and some yield another crop in June.

Rhubarb can be red to pink to even slightly green. The stalk is the only edible part of this summer fruit, uh, vegetable — the leaves are poisonous.

Rhubarb is super sour, like cheek puckering sour, and so is typically cooked with sugar, since it is super sour on it’s own.

What does rhubarb taste like?

Rhubarb when raw, is crunchy and super sour. It is typically cooked with sugar, softening and sweetening it up into a wonderful sweet-tart treat.

The bright red stalks of rhubarb have a stronger, sweeter more robust flavor than green stalks, but both are totally fine to cook with, which means you don’t have to do a lot of guessing when it comes to harvesting.

When is Rhubarb Season?

Rhubarb season begins in late spring through early summer, rhubarb season might be short, but rhubarb freezes extremely well and can easily be used in this strawberry rhubarb dump cake or any of your favorite desserts.

Is rhubarb a vegetable or fruit?

Well even our government was a bit confused about this, at least with regard to import tax purposes. In 1947 the US Customs Court in Buffalo, NY ruled that while rhubarb is legally a vegetable, for customs and tariff purposes ruled it a fruit since the majority of consumers used it in rhubarb desserts.

Simple Ingredients for Rhubarb Cake with Cake Mix

Full list of measurements and instructions in the printable recipe card at the end of this post.

• Rhubarb | Fresh or Frozen, if using frozen do not thaw.
• Cake Mix | I used Yellow cake mix, White cake mix and Vanilla Cake mix in my testing, I liked Vanilla the best personally.
• Sugar | I used organic cane sugar, but you may use regular white sugar
• Cornstarch | Just a touch to help create a thick slurry with all of the rhubarb juices.
• Butter | Use a good quality butter here, you may melt and pour it over, or slice into ⅛ inch slices and layer across the top of the cake.
• Nutmeg | this ingredient is optional, but I believe adds a light nuttiness to the rhubarb cake.
• Strawberries | (optional) use sliced fresh strawberries, frozen or even try other berries in this quick dessert

How to Make Rhubarb Dump Cake Recipe

Heat oven to 350 degrees F and using nonstick cooking spray, spray 9×13 inch pan, or 2 quart casserole dish — the smaller casserole dish will take a bit longer to bake, and might be slightly gooey in the middle, but it’s still amazingly delicious!

Lay the fresh or frozen (do not thaw) rhubarb in the bottom of the baking dish, sprinkle sugar and cornstarch evenly over the top, then gently toss to coat the rhubarb with the sugar and corn starch mixture. Sprinkle with fresh grated or ground nutmeg if desired.

Next, evenly sprinkle the cake mix over the top of the rhubarb mixture. DO NOT MIX! Use your fingers to even out the cake mix without pressing it down.

As evenly as possible, drizzle the melted butter over the top of the dry cake mix, or you may slice the same amount of cold butter and layer it evenly over the cake as in my Caramel Apple Dump Cake.

Bake for 45 – 60 minutes in preheated oven, until golden and bubbly.

Remove from oven and allow to cool about 15 minutes before serving.

It was a toss up with my recipe testers, some loved it warm (I did) and others loved it cold!

No matter how you enjoy it, with a scoop of vanilla ice cream or a dollop of whipped cream, you will fall in love with this easy dessert.

Recipe Testing the Best Rhubarb Cake with Cake Mix

This super easy dessert took me 3 tries before I was satisfied! Not because there aren’t some great recipes out there, but I wanted to use less sugar, make without Jello and have it still be delicious.

1. My first attempt I used water, cornstarch and an all natural cake mix, covered with foil — resulting in a cake that was spongy, gooey and the rhubarb too gummy.
2. Second test, I used regular cake mix, water, baked in a smaller dish, omitted the cornstarch, the cake topping was perfect, golden with a slight crunch — however the inside was liquid! It tasted amazing, but would get soggy in a heartbeat.
3. My final attempt, I baked in a 9×13 dish, omitted the water, used less sugar, (it’s already quite sweet) a little cornstarch and added an additional quarter cup of butter — I loved this one the best! I will try it again in a smaller dish as I personally like a bit more rhubarb in my serving, or double up on the amount of rhubarb

Storage

Cool on the counter, then store in the refrigerator covered tightly with plastic wrap. On the counter for 1 day, in the fridge up to 7 days, this dump cake recipe freezes well too. Seal well nad freeze up to 3 months.

Frequently Asked Questions

High Altitude Rhubarb Dump Cake

The only adjustment needed for this recipe for high altitude is you may have to bake this a bit longer at higher altitudes.

More great Dump Cake Recipes

• Easy Caramel Apple Dump Cake Recipe
• Lemon Dump Cake Recipe
• Easy Pumpkin Dump Cake Recipe
• Easy Fresh Peach Dump Cake Recipe

Easy dessert recipes

• Best Oreo Dessert Pudding (No Cool Whip)
• The Best Easy No Bake Banana Pudding Recipe (Magnolia Banana Pudding)
• Moose Tracks Ice Cream Recipe {No Churn}
• No Bake Lemon Icebox Pie Recipe
• The Best Key Lime Pie
• Easy Homemade Chocolate Ice Cream Recipe

I’m so glad you are here with me today, be sure to print the recipe card below and if you make the rhubarb dump cake recipe, please, please, give it a 5 star rating and comment.

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