Rhubarb dump cake is an inelegant (read: gross) name for a dessert as delicious as this one.
And guess what? It takes barely five minutes of active time to put together! Even if you’re baking-inept you can totally make this successfully. You don’t even need to stir anything or dirty a bowl! (Life’s better with fewer dishes to wash.)
Dessert doesn’t get any easier unless you buy it at the grocery store. You literally just layer all the ingredients in a baking dish, pop it in the oven, chill it for a bit, then serve.
And maybe cry a little bit because it’s just.that.good. I mean, is it even summer if you don’t bake with rhubarb at least once?
Why you’ll love this rhubarb dump cake:
- It doesn’t even take five minutes to assemble
- No mixer necessary!
- It’s unbelievably easy and anyone can make it successfully
What is rhubarb?
If rhubarb is new to you, let me explain a bit. Rhubarb is technically a vegetable and it kind of resembles red celery. But here’s the thing: while it’s technically a veggie, it’s legally a fruit. Confused?
Turns out in 1947 the U.S. Customs Court in Buffalo, NY, ruled that because rhubarb is typically used as a fruit (e.g. in sweet pies) it should be considered a fruit for tax purposes. (This meant rhubarb importers could pay less in tax since vegetables were taxed at a higher rate.)
So what does rhubarb taste like? It’s very, very sour. Unless you love sour things you really need to add some sugar to it. But under the sour is a really pleasant fruity taste that pairs really well with berries.
And in fact, rhubarb is delicious just cooked down in a saucepan with a little bit of sugar and nothing else. I use that to top yogurt and oatmeal—and often I just eat it by the spoonful.
Can I use other fruit in this dump cake?
YES! Making a rhubarb cake isn’t your only option. In my family this dessert is actually know as “dad’s fruit cobbler” and we usually make it with blackberries (it’s delicious).
Just swap in berries (or even pitted cherries) for some or all of the rhubarb—there’s no need to make any other changes. You could do strawberry-rhubarb or blackberry-raspberry or whatever else you can dream up. The possibilities are endless!
How to make rhubarb dump cake
I almost feel silly posting step-by-step pictures for this recipe because it’s so simple. But just in case it helps you to visualize, here you go.
- Start by arranging chopped rhubarb (you can use fresh or frozen) in a 13-by 9-inch baking dish.
- Sprinkle strawberry jello (or any red jello) over the rhubarb, then top with granulated sugar.
- Top with yellow cake mix (or white cake mix), then melted butter, then cold water.
- Bake for about an hour, until the fruit is bubbling.
You can serve this warm but it’s much easier to serve if you refrigerate it for a few hours to let the fruit set up.
And since this rhubarb dump cake lasts for several days in the fridge you can totally make it a day ahead. I actually think the flavor improves if it’s refrigerated overnight.
And there you have it: rhubarb dump cake. It really needs a different name. . .I think I’ll just refer to it as “the best thing ever.” Because it SO IS! If you’re a rhubarb lover you really need to try this sometime soon.
A few more fruity desserts:
Strawberry Rhubarb Cheesecake Pie
Cherry Crumb Pie
Fresh Peach Dump Cake
Strawberry Shortcake Layer Cake
Raspberry Cupcakes
Did you make this rhubarb dump cake? Great! Let me know what you think with a comment and a rating below. And post a pic on Insta–tag @theitsybitsykitchen so I can see your creations!
This rhubarb dump cake is an easy dessert that anyone can make with success! It's a sure crowd-pleaser!
- 4 cups sliced fresh or frozen rhubarb from about 15-16 ounces
- 3- ounce box strawberry jello or any red jello
- 3/4 cup granulated sugar
- 1 15.25-ounce box white or yellow cake mix*
- 1/2 cup butter melted (salted butter is better here)
- 2 cups cold water
- Preheat the oven to 350 degrees. Lightly spray a 13- by 9-inch baking dish with cooking spray.
- Arrange the rhubarb in an even layer in the bottom of the baking dish. Sprinkle the jello over that, then top with the sugar.
- Sprinkle the yellow cake mix powder over all of that, then top with the melted butter and the cold water. Bake for 45 minutes to an hour, until the top is lightly browned and the rhubarb is bubbling.
- It’s possible to serve the dump cake warm but it’s MUCH easier to serve if you chill it for a couple of hours, until it sets up a bit. Serve with whipped cream or ice cream if desired.
- Uneaten cake can be stored in the fridge, covered, for up to 4 days or frozen (tightly wrapped) for up to 2 months.
Recipe Video
*I used Duncan Hines classic yellow
Laurie says
My rhubarb is frozen and as it thaws it is getting a bit of rhubarb juice in the bag. Can I use that liquid as part of my 2 cups water. I would think it would add to the flavor.
Kelsie says
Hi Laurie! It’s best to use the rhubarb straight from frozen.
Joy says
I loved the recipe but it was a little sweet so I had it with plain Greek yoghurt. Could I make it with less sugar or none at all.
Kelsie says
You can absolutely make it with less or no sugar. I’m glad you enjoyed it!
Donna says
I have a rhubarb plant that is 6 feet across, and I’m always looking for something else to do with it! I made this recipe for a family dinner, but I was a bit nervous about the “clumping” mentioned by another poster. I opted to mix the butter, water and cake mix before pouring it on, and it turned out great! The texture was excellent – almost chewy, and the rhubarb/Jello mix added a nice bit of tartness. The whole family loved it, and I’m going to start picking and freezing my rhubarb so we can eat this all winter long!
Sabrina Lynn says
Hi! When I made this for the first time tonight, some of the cake mix was still uncooked and powdery in lumps on top when it was done. I followed the recipe exactly. Any advice? I mixed a bit more melted butter with some milk and kinda painted it on those spots with a pastry brush, then put it back in for 5 more min. It helped but how do I avoid that happening in the future? I had carefully poured the water over everything to try to make sure it was all wet but it didn’t stay just on top of the cake mix, and instead did as water likes to do and filled in all the cracks below first.
Kelsie says
That just happens sometimes with a dump cake like this; to avoid it in the future you can mix the cake mix, melted butter, and water in a mixing bowl until it’s smooth, then pour it over the rhubarb.
Bethany York says
I’ve made this once, and I did have the issue with clumping on top. I ended up making whip cream to cover the whole top with, and it was delicious! I’m making it again tomorrow, and I just wondered if mixing the cake mix with the butter and water is going to make it have more of a cake like consistency? When I made it before it was more of a cobbler consistency.
Tarron says
Question to all who have made this: Does this set up firm on the fridge? Can I slice it and portion it for a party or is it more of a custard type consistency when cool? Basically, will I need bowls and spoons or plates and forks? Lol
Kelsie says
If you serve it cold, it will be pretty firm so you should be fine with either plates or bowls. If it’s room temp, it will be a little looser.
Susanne Amato says
Instead of melting butter, can I put squares of butter on top?
Kelsie says
I’ve never tried it that way but it could work.
Grace says
I do! I followed a tip on another dump cake recipe, and grated thin butter layers over top, completely covered it. I used maybe twice the butter, but I’m not counting calories with this. It works out great! Easier than melting and trying to cover the cake mix without stirring.
Barb Childers says
My husband did not like rhubarb, until I made this. It has won him over. This is a great easy recipe. I had a white off brand cake mix. It worked fine. Used strawberry Starburst Jello. It was delicious.
Kelsie says
Haha! I’m so glad you converted him!
Diana says
Can you freeze any left overs….senior on her own
Kelsie says
Yes, you can freeze it. I recommend using individual containers to freeze the portion size you want because it’s hard to scoop when it’s frozen; you can heat it in the microwave or just let it sit on the counter for awhile to thaw. Be sure to cool it completely before you freeze it though!
Bev Slager says
Can I use sugar free jello?
Kelsie says
That should be fine!
Jean says
Can I use raspberry Jell-O instead?
Kelsie says
Absolutely!
Jean says
Thank you !! It’s delicious !!
Kelsie says
I’m glad you enjoyed it!
Carol says
I’m baking this right now and it is not setting. The top is golden but the rhubarb mix is liquid. Help!
Kelsie says
It won’t set until it’s out of the oven cooling–the liquid will be very bubbly when it’s hot. As long as you followed the recipe you should be fine!
Karen says
Just made for the first time. It’s so good. Can it sit on the counter covered or put it in the refrigerator ?
Kelsie says
I’m so glad you enjoyed it! Definitely store it in the fridge rather than on the counter.
Rick W says
my mom used to make the best rhubarb pie , never made this cobbler like goodie . and now that im diabetic im going to substitute everything with sugar free ingredients .
im will be using splenda or truvia , should i lower amount of sugar substitute since they seem sweeter than regular sugar ?
i just found this recipe and cant wait to try it
Kelsie says
I don’t regularly use Splenda or truvia so I can’t give you good advice on how much to add but the bag or box should tell you if it’s a 1:1 substitution. I hope you enjoy the recipe!
Rick W says
my store finally had rhubarb so i made it for memorial day weekend . i used all sugar free ingredients , sugar free jello , splenda and sugar free yellow cake mix . i have nothing to compare it to cause ive never had a dump cobbler with rhubarb .
it is FANTASTIC
sweet and tasty and jumped to my number 1 cobbler to make
thanks for the recipe although i altered it slightly
Kelsie says
Hooray! I’m glad you finally got your hands on some rhubarb and enjoyed the recipe!
Cindy says
I’ve been making it for the last couple of years with sugar free products. I use the truvia and use less sugar more than the package suggested but less then the 3/4 cup. It’s wonderful to find deserts that is diabetic friendly!
Helen John says
Do I need to thaw the rhubarb? please advise.
Kelsie says
If you’re using frozen rhubarb, don’t thaw it first. Hope you enjoy the recipe!
Barb says
Thank you for posting this question/answer!!
Blake says
SO GOOD! Made today for the fourth and it turned out amazing. Decreased the sugar like some comments said and it was perfect! Definitely an easy bake and super delicious!
Kelsie says
Yay! It’s one of my favorites. I’m so glad you liked it!
PJ says
Made my first one As a practice for my husband and myself and it was very good but I thought a little sweet so I decreased the sugar by a quarter cup of sugar for the one I making for coffee tomorrow. I think it will be perfect. Thank you. PJ from Remer
Kelsie says
I’m so glad you liked it, PJ!
Debra Clements says
I followed this recipe. It was so easy and delicious. Definitely will make again.
Kelsie says
I’m so glad you liked it, Debra! Thanks for letting me know!
Christine says
This recipe is super easy. The finished product is perfect; just the right sweetness & tangy rhubarb flavor. I had some for breakfast. Yum! I followed the recipe exactly. I wouldn’t change a thing .
Diya says
This looks good! I have never tasted rhubarb. I’m kinda scared of it, lol. I’ve always wondered what something like Strawberry Rhubarb tastes like, but then I’m worried I’ll hate it, which seems ridiculous, lol. What does it taste like?
Kelsie says
Hi Diya! As long as you add sugar, rhubarb is DELICIOUS so don’t be scared! It’s really sour on its own but with some sugar to tame it, it’s just pleasantly tangy and fruity. I don’t really know how to describe the flavor other than that. If you don’t want to commit to making the cake in case you hate it, you could just try cooking some rhubarb down in a saucepan–maybe a half cup of chopped rhubarb with a couple tablespoons of sugar and a teaspoon of water. Cook it on medium heat until it gets mushy and has broken down quite a bit, then taste it. I eat it like that over yogurt or just by itself all spring and summer. And if you like it, then great–you can make the cake! I hope you end up loving it like I do!
Donna L Downing says
I grew up eating rhubarb out of my dad’s garden. As kids, we were permitted to pick some when we got hungry during play. I carrierd a little plastic salt shaker in my back pocket. The transition to cooked rhubarb in a dessert or beverage is magical. Cooked with sugar it becomes a slightly tart, yummy treat. I’m lucky to have a cutting from my dad’s plants in my back yard.
Erika says
This looks absolutely incredible! And I wish I could get my hands on rhubarb here in Texas because I’m wanting to try this desperately!