Banana Cake with Chocolate Frosting

Coffee banana cake flavoured with coffee and topped with milk chocolate frosting

4.50 from 2 votes

Banana Cake with Chocolate Frosting

Learn how to make the best banana cake with chocolate frosting with this easy recipe. The moist banana cake is made with sour cream and the chocolate fudge frosting is flavoured with espresso powder and sour cream for a very flavourful topping.

Prep Time30

Cook Time35

Total Time1 5

Course: Dessert

Cuisine: American

Servings:

Calories: 559kcal

Author: Janice Lawandi

Equipment

Ingredients

For the coffee banana cake

173 grams unsalted butter softened
100 grams granulated sugar
100 grams light brown sugar
2 large egg(s)
350 grams mashed banana from 3–4 large bananas
60 ml sour cream (14% fat)
10 mL pure vanilla extract
250 grams cake flour
23 mL ground coffee beans
10 mL baking powder
2.5 mL Diamond Crystal fine kosher salt
1.25 mL baking soda

For the milk chocolate frosting

58 grams unsalted butter
65 grams milk chocolate (41 % cocoa content)
140 grams icing sugar sifted
85 grams sour cream (14% fat)
23 grams Cacao Barry extra brute cocoa powder
5 mL instant espresso powder
5 mL pure vanilla extract
1.25 mL Diamond Crystal fine kosher salt

Decoration (optional)

30 grams candied nuts chopped, or toasted nuts chopped

Metric - US

Instructions

To make the coffee banana cake

Preheat the oven to 350ºF (175 °C). Grease a 9x9-inch (23x23 cm) metal brownie pan (I used a Chicago Metallic pan you can find on Amazon). Line the bottom with parchment paper. Flour the sides of the pan if you find your cakes stick. Set aside.
In the bowl of an electric mixer fitted with the paddle attachment or with an electric hand mixer, cream together the butter and the sugars. Scrape down the sides of bowls as needed.
Add the eggs one at a time and beat them in. The mixture should be fluffy and well mixed
Mash together the bananas with the sour cream and vanilla.
In a separate bowl, whisk together the flour with the baking powder, baking soda, the coffee grounds, and the salt. You can also sift the dry ingredients if they are very lumpy, but note the salt and coffee grinds won't go through the sieve, so add them after sifting or transfer what is trapped to the bowl of dry ingredients.
Alternate mixing into the cake batter the dry and wet, beginning and ending with dry ingredients. Mix until the batter ingredients are combined. Do not overmix!
Transfer the batter to the prepared pan and smooth the surface with a mini offset spatula .
Bake the cake for about 35 minutes until the edges are golden brown and a cake tester inserted in the centre comes out clean. Let cool 10 minutes then unmold onto a wire rack.

To make the milk chocolate frosting

Melt together the butter with the Alunga chocolate on power level 5 of the microwave or over a double boiler. Set aside to cool slightly.
Beat together the melted chocolate mixture with the rest of the ingredients into a smooth frosting
Once the cake has completely cooled, smooth the frosting over top and decorate with candied or toasted nuts or even sprinkles.

Notes

This recipe calls for Diamond Crystal fine Kosher salt. If using regular table salt, add half the amount or the recipe may be too salty!
I baked this in a square 9x9-inch (23x23-cm) cake pan. Be sure to butter it and flour it, lining the bottom with square of parchment paper to make the cake easier to serve.
Transfer the batter to the prepared pan and smooth the surface with a mini offset spatula.
For the chocolate in the frosting, I've tested the recipe with both milk or dark chocolate and it works! Please use high-quality chocolate with a higher percentage of cocoa solids (at least 40 %). Otherwise, the frosting may lack flavour and be too sweet!
Want to add nuts? You can add chopped nuts to the banana cake batter, for example chopped roasted peanuts or toasted walnuts would be excellent here
Coffee—don't like coffee? Skip the coffee grinds and the espresso powder. The coffee grinds in the cake batter create a lovely flecked cake, reminscent of the banana seeds. The espresso powder in the frosting is discrete, but you can skip it altogether if you would prefer.
Garnishes—I've topped this cake with candied pecans, chopped nuts, but also chocolate sprinkles. Use what you've got! Chopped popcorn brittle also makes a fun garnish.

Nutrition