Peanut Butter Banana Cake

5 from 1 vote

Peanut Butter Banana Cake

This luscious Peanut Butter Banana Cake is the perfect cake to feed a crowd! A simple, one layer banana cake made on a large sheet pan baked until golden brown, then slathered in a luscious peanut butter cream cheese frosting. Totally irresistable, and super easy to make!

Prep Time30

Cook Time30

Cooling time (for cake)1

Total Time2

Course: Dessert

Cuisine: American

Diet: Vegetarian

Servings: servings

Calories: 340kcal

Author: Briana

Equipment

15x21-inch baking sheet
hand mixer (or stand mixer with paddle attachment)
offset spatula
digital kitchen scale

Ingredients

Cake

1 cup milk (can be subbed for buttermilk. If using buttermilk omit vinegar and add 1.5 tablespoons of buttermilk)
1.5 tablespoons apple cider vinegar sub white distilled vinegar
2.5 cups all purpose flour 300 grams
1 ½ teaspoons baking powder
½ teaspoon baking soda
1 teaspoon kosher salt
¾ teaspoon cinnamon optional
1.5 cups ripe bananas, mashed (About 3 large bananas, but will depend on the size of the bananas you have. You need about 340 grams total).
½ cup unsalted butter softened (1 stick)
1 ¼ cups granulated sugar
½ cup light brown sugar
¼ cup avocado oil sub other neutral oil
3 large eggs room temperature
1 tablespoon vanilla extract

Peanut butter cream cheese frosting

½ cup unsalted butter softened (1 stick)
8 ounces cream cheese room temperature (1 block)
¾ cup creamy peanut butter standard, like JIF
½ teaspoon kosher salt
2-3 cups powdered sugar as needed and to taste
1 tablespoon vanilla extract
Crushed peanuts and banana slices for topping

Instructions

Banana cake

Preheat the oven to 350°F. Grease a 15x21-inch baking sheet and set aside.
In a small container, combine 1 cup milk and 1.5 tablespoons of apple cider vinegar to make homemade buttermilk. Set aside while you work on the rest of the cake.
In a separate small bowl, mash together the bananas using a hand mixer, or by hand. You will need a total of 340 grams or 1.5 cups of mashed banana. Please be sure to measure as banana sizes vary.
In a separate small bowl, whisk together 2.5 cups of flour, 1.5 teaspoons of baking powder, ½ teaspoon of baking soda, 1 teaspoon of kosher salt, and ¾ teaspoon of cinnamon (optional). Set aside.
Using a handheld electric mixer or a stand mixer with the paddle attachment, beat 1 stick of unsalted softened butter, 1.25 cups of white sugar, and ½ cup of brown sugar on medium speed until beginning to come together—about 3-4 minutes. Make sure to scrape the bowl a couple of times to ensure everything is incorporated. It will be a bit lumpy at this point.
Add the 3 eggs, 1 tablespoon of vanilla, and ¼ cup of avocado oil. Beat on medium-high speed until completely incorporated. Next, mix in the mashed bananas. Scrape down the sides and up the bottom of the bowl to ensure everything is completely incorporated.
Sift in about a third of the dry ingredients, and mix with the mixer on low until just combined. Then, add in about a third of the homemade buttermilk mixture and combine gently. Continue alternating the dry ingredients and the buttermilk and mix on low speed until each addition just until incorporated. Do not overmix, or the cake will become dense. The batter will be thick, and it may have a few lumps.
Pour the batter into the prepared baking dish and smooth the top using an offset spatula or rubber spatula. Bake in the preheated oven for 25-30 minutes or until a toothpick inserted into the center comes out clean.
Once the cake is done, remove it from the oven and let it cool completely in the baking pan on a wire rack.

Frosting and serving

Meanwhile, make the frosting while the cake is cooling. In a mixing bowl, mix together the 1 stick of softened butter for about 4 minutes until smooth using a hand mixer or a stand mixer with the paddle attachment. The butter should become light fluffy and pale in color.
Add 8 ounces. ofcream cheese, and cream together for an additional 3-4 minutes, until the mixture is completely soft and free from lumps. Make sure to scrape the sides of the bowl a few times.
Add in ¾ cup of peanut butter, most of the powdered sugar (about 2 cups), 1 tablespoon of vanilla extract, and ½ teaspoon salt. Mix together until nice and smooth. Add more powdered sugar if desired for a thicker texture or sweeter taste.
Once the cake has cooled completely, frost it and dig in!
Store leftovers in an airtight in the container in the fridge for up to 5 days.

Notes

Use room temperature ingredients for the cake batter. Ingredients at room temperature will mix together much more smoothly. Set out the milk, eggs, and butter ahead of time so they aren’t super cold.
For the frosting, we prefer working with cold or slightly softened butter and cream cheese. Cream cheese frosting can become a little runny over time, but for frosting that is on the stiffer side, take it out of the fridge about 20 minutes before using, and that’s it. You want the butter and cream cheese to be quite cold so that they hold their shape.
Alternate dry and wet ingredients. When adding the flour mixture and homemade buttermilk, this method ensures even incorporation without overmixing.
Measure accurately. Use a kitchen scale if you have one, as the sizes of cups vary. Accurate measurements can take a baked good from good to great!
Use a standardized creamy peanut butter. We like using JIF for consistent results. Natural peanut butter won’t work as well because there is a lot of variation between different brands. Some brands will be more oily than others, and that can impact the final texture of the frosting. I do not suggest using crunchy peanut butter.

Nutrition