Step 1

Preheat oven to 350˚ F. Using a baking spray, generously grease the cake pan(s). For a 2-layer cake, you can bake this cake in two 4, 5, or 6-inch cake pans, or in a 9x13-in rectangular pan and cut the circle as I show in the photos above (see notes for more details).

Step 2

In a large bowl, whisk together flour, baking powder, baking soda, and salt. Set aside.

Step 3

In a mixing bowl, combine milk and vinegar. Let the mixture stand at room temperature for 5 -8 minutes. When it is ready, the milk will be slightly thickened, and you will see small curdled bits. Reserve.

Step 4

In a large bowl, beat butter until creamy on medium-high speed for about 3 minutes. Scrape down the sides and up the bottom of the bowl with a rubber spatula as needed. Add maple syrup mashed banana and vanilla; continue beating to combine.

Step 5

Reduce speed to low and add half of the flour mixture. Scrape down the mixing bowl with a spatula and turn the batter over several times to ensure all of the ingredients are well incorporated. Add milk mixture; continue beating to incorporate. Add the remaining flour; beat just until combined. Do not overmix this batter.

Step 6

Pour the cake mixture into the prepared pan(s). Bake until a skewer comes out clean when poked in the center. Baking times will vary, depending on what kind of pan you use, so keep an eye on yours. The cake is done when a toothpick inserted in the center comes out clean. For 2 small round cake pans bake for about 18-21 minutes. For a 13x9 rectangular pan bake for 20-25 minutes.

Step 7

Allow cake to cool completely in the pan set on a wire rack. The cake must be completely cool before frosting.

Step 8

I used my easy Vanilla Buttercream to frost this cake. If you prefer chocolate, I have a Chocolate Buttercream recipe too.

Step 9

If your cakes are not leveled, use a large serrated knife, slice a thin layer off the tops of the cakes to create a flat surface.

Step 10

Place 1 cake layer on your cake stand. Evenly cover the top with frosting (about 3/4 cup). Top with 2nd cake layer and evenly cover the top with frosting. And so on, until you're done with all the layers you made.

Step 11

Spread the remaining frosting all over the top and sides.

Step 12

Decorate as your heart desires.