This chocolate chip banana crumb cake is tender and moist, making a delicious brunch baked good or dessert. Covered in a rich and buttery crumb topping, this crumb cake recipe will be a family favorite.
Two weeks ago it was all about crumb topping, so I couldn’t leave you hanging on the crumb cake itself. In traditional recipes, the cake portion isn’t exactly groundbreaking or where the emphasis lies. I mean, with a a crisp and buttery layer of crumbs on top, why would it be?
The cake in crumb cake tends to be an afterthought. But! It doesn’t have to be.
Each week I buy a few bananas and purposely let them languish in the fruit bowl until they’re overripe. Really as overripe as they can be without ending up in the trash can.
Now my standard overripe banana recipe is this naturally sweetened banana bread, but rather than add another half a loaf to my banana bread freezer stash, I started thinking about more of a dessert baked good.
Combine this with a hankering for crumb cake, and here we are. Chocolate chip banana crumb cake.
Easy ingredients and steps
This crumb cake begins by creaming together room temperature butter and granulated sugar until creamy and fluffy, setting the stage for a perfectly cake-y baked good.
Next mix in the rest of the wet ingredients, including mashed banana, buttermilk, an egg and vanilla extract.
Thanks to buttermilk and a full cup of mashed banana, this crumb cake is a bit moister than the cake layer in a traditional crumb cake. And don’t tell anyone I said this, but that’s a welcome change as far as I’m concerned. 😉
Now it’s time to add the dry ingredients, including all-purpose flour, baking powder, baking soda, and salt. Mix them in until just combined, taking care not to overmix. The reason for this is when the flour hits liquid, the gluten starts activating. Overmixing the batter can cause the gluten to strengthen more than you’d like for a cake, leading to drier baked goods with a tougher crumb. Not what we’re after here.
Let’s leave the healthy banana baked goods (like these freezer-friendly whole wheat banana chia muffins) for another time and pile on to the more decadent nature of this banana crumb cake and add some chocolate.
I used mini semisweet chocolate chips for a less intense chocolate taste. There aren’t any huge chunks of chocolate to bite into that will dominate the flavor, you know? But be my guest and use regular-sized chocolate chips or chunks if that’s what you prefer. There’s no right answer.
Once you pour out the batter into the prepared (greased and floured) pan, it’s crumb time.
The particular crumb cake you see in these photos was made using one whole batch of crumb topping, which is linked right in the recipe card below.
While there is enough to cover the top surface generously, it isn’t piled super high like good old New York crumb cake. If that’s the look you’re going for, I suggest doubling the crumb topping recipe and going to town!
Once baked, let the crumb cake cool in the pan completely before slicing into squares and dusting with powdered sugar.
- It’s important to use buttermilk here instead of just regular milk, because the acidity is needed to react with the baking soda so this crumb cake can rise in the oven.
- See the notes in the recipe card below on how to make a quick and dirty DIY buttermilk at home from the milk of your choice and either white vinegar or lemon juice.
- Double the crumb topping recipe if you want a SUPER thick layer of crumbs on top.
Chocolate Chip Banana Crumb Cake
- 1/2 cup unsalted butter at room temperature
- 3/4 cup granulated sugar
- 1 cup mashed banana, from about 3-4 medium bananas
- 1/2 cup buttermilk (see note on DIY)
- 1 egg
- 1 1/2 tsp vanilla extract
- 1 1/2 cups all-purpose flour
- 1 tsp baking powder
- 3/4 tsp baking soda
- 1/4 tsp plus 1/8 tsp salt
- 3/4 cup mini chocolate chips
- 1 batch crumb topping (or two batches, see note)
- Confectioners' sugar for topping
- Preheat oven to 350°F. Grease and flour an 8"x8" square pan.
- Cream softened butter and sugar in a large mixing bowl for a few minutes until fluffy.
- Add mashed banana, buttermilk, egg, and vanilla extract and mix in.
- In a separate mixing bowl, whisk together flour, baking powder, baking soda, and salt.
- Add the dry ingredients into the bowl with the wet ingredients and mix until just combined. Stir in chocolate chips.
- Pour out mixture into the prepared pan, smoothing the top with a spatula.
- Prepare crumb topping according to recipe instructions (link in the ingredient list above). Evenly scatter crumb topping over top of the crumb cake.
- Bake for 35-40 minutes, or until a tester inserted in the center comes out clean. Let cool in the pan before slicing. Dust with confectioners' sugar just prior to serving.
Nutritional information is provided as an estimate. As it can vary due to many factors (brands used, quantities, etc.), we cannot guarantee its accuracy.
Cake portion adapted from The Kitchn.