Preheat the oven to 350F and line a 9x13 pan with parchment.
In a large bowl, beat together the butter, oil and both sugars until light and pale, a minute or two.
½ cup unsalted butter, ¼ cup neutral oil, ¾ cup white granulated sugar, ¼ cup brown sugar
Crack in the eggs and beat until well combined. Lightly mash the bananas and stir them in and add in the vanilla.
3 large eggs, 1 ¼ cup mashed bananas, 3 large, 1 teaspoon vanilla extract
Add in the buttermilk and mix until well incorporated.
1 ¼ cup buttermilk
In a small bowl, combine the flour, baking powder, baking soda, salt, and cinnamon.
1 teaspoon baking powder, 1 teaspoon baking soda, ½ teaspoon cinnamon powder, 2 ½ cup all purpose flour, ½ teaspoon salt
Add the dry ingredients to the wet and gently mix until it's just combined. Do not over mix.
Pour the batter into the prepared baking pan evenly and bake for 35-40 minutes, or until a toothpick inserted comes out clean.
Let the cake cool completely.
Whip the heavy cream until it slightly thickens. Add in the powdered sugar and vanilla extract and beat until it forms slightly stiff peaks.
1 ¼ cup heavy cream, 5 tablespoon powdered sugar, to taste, ½ teaspoon vanilla extract
Evenly spread around ½ a can of the dulce de leche in a generous layer. Place the banana slices on the dulce de leche.
1 can dulce de leche - 300ml, 3-4 bananas, sliced
Spread the whipped cream on top of the bananas in an even layer and top it off with some more drizzled dulce de leche!
Cut and enjoy!
