Rhubarb Cake with Cinnamon Sugar Crunch Topping


It's rhubarb season!  This is a little bit different twist on a rhubarb snack cake.  The crunchy butter/sugar/cinnamon topping adds extra flavor, taking it right over the top.  That being said, you can certainly make it without, and you will have a deliciously moist rhubarb cake.

About the ingredients:

- Cinnamon Sugar Crunch Topping - you can absolutely omit this.  If you do, omit the butter and 1/2 teaspoon cinnamon and add the 1/4 cup of granulated sugar to the flour mixture in step 5.

- Milk - this can be any kind of milk, including plant-based.  Don't have milk on hand?  No worries, you can sub with water, and it will still taste delicious.  Milk adds a bit of richness, but we've tried this with water, and it is still incredible.

- Rhubarb - to peel or not to peel?  That's up to you but I, personally, peel my rhubarb.  I just grab an end with the blade of a small sharp knife and pull the outer stringy peel off.  I do this for each side, not bothering with any bits of peel that remain.

- Oil - if you would prefer to make this lower fat I have successfully subbed half of the oil with applesauce.  I haven't tried substituting the entire amount because usually that makes it quite dense, but you could certainly try if you like.  Use any liquid oil.  If using something solid such as coconut oil or butter, just melt it first.

- Sugar - this recipe is easily adaptable to whatever sweetness you prefer.  You can easily cut down the sugar - I would cut it from the sugar you add to the flour mixture.  Or, if you would like to cut down on the sweetness, as noted above you can omit the cinnamon sugar crunch topping (and don't add that additional sugar to the flour mixture.  We find this recipe to be sweet, which balances the tartness of the rhubarb.

printable recipe here

Rhubarb Cake with Cinnamon Sugar Crunch Topping
makes: 1- 8"x8" cake

1 teaspoon vinegar (white or apple cider)
1 cup milk (any kind)
2 cups rhubarb, chopped small
1/2 cup granulated white sugar, divided
1 1/2 cups all-purpose flour
1 teaspoon baking soda
1/2 teaspoon salt
1/2 teaspoon cinnamon
2 teaspoons vanilla extract
5 Tablespoons liquid oil (see note above)

Cinnamon Sugar Crunch Topping:  (optional, see note above)
1 Tablespoon butter
1/4 cup granulated white sugar
1/2 teaspoon cinnamon

1. Preheat oven to 350 degrees F.  Prepare an 8"x8" square baking pan with oil/butter/non-stick cooking spray.  Set aside.

2. Prep the rhubarb:  In a medium bowl, add the chopped rhubarb and 1/4 cup of the sugar.  Stir to coat all rhubarb.  Set aside.

3. Prep the milk mixture: In a measuring cup or small bowl, combine the 1 cup milk and 1 teaspoon vinegar.  Set aside.

4. Prepare the Cinnamon Sugar Crunch Topping: In a small bowl, melt the 1 Tablespoon butter.  Stir in the 1/4 cup sugar and 1/2 teaspoon cinnamon.  It should look like wet sand.  Set aside.

5. Mix the dry ingredients:  In a large bowl, combine the remaining 1/4 cup sugar, flour, baking soda, salt, and 1/2 teaspoon cinnamon.  Whisk together.

6. Add wet to dry ingredients: To the flour mixture, add the milk and vinegar mixture, vanilla, and oil.  Stir until almost fully incorporated, then add rhubarb and sugar mixture.  Stir until all flour has been fully mixed in.

7.  Pour cake mixture into prepared baking pan.  With your fingers, sprinkle the cinnamon sugar crunch topping over the top of the cake mixture.  It's ok if there are some lumps in the cinnamon sugar mixture, it will add delicious crunch pockets to the finished cake!  (you can see in the photos all of these coveted pockets!)

8. Bake on the middle rack of the oven for 30-35 minutes.  Check the center of the cake with a toothpick to make sure it comes out clean.  Cool on a cooling rack.


  1. Thank you, Staci for the recipe-I’m the only one who likes rhubarb, that means there’s more for me! Have a good weekend-I bet you’re doing what I’m doing - battling heat, humidity, and weeds😅!

    1. Mary, that's a bummer that you're the only one in your family who enjoys rhubarb. You are right though....more for you. Yes, pretty much doing exactly that. lol Hoping you had a wonderful weekend!


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