- 1 teaspoon shortening
- 2 cups all-purpose flour
- 1 teaspoon baking soda
- 1 teaspoon baking powder
- 1/4 teaspoon salt
- 1/4 cup butter, room temperature
- 1 1/3 cups white sugar
- 2 eggs, at room temperature
- 1 cup sour cream
- 1 cup mashed bananas
- 1 teaspoon vanilla extract
- Preheat oven to 375 degrees F (190 degrees C). Position oven rack in the center of the oven. Grease a 9×5-inch loaf pan with shortening.
- Whisk flour, baking soda, baking powder, and salt together in a bowl.
- Beat 1/4 cup butter in the bowl of a stand mixer on medium speed until smooth. Slowly pour sugar into the butter and continue beating until light and fluffy, about 2 minutes. Add eggs, 1 at a time, and beat until combined. Beat sour cream, mashed bananas, and vanilla extract into butter mixture until combined, about 1 minute.
- Gently fold the butter-banana mixture into flour mixture until just combined. Pour batter into the prepared loaf pan and smooth the top. Tap the loaf pan on the counter to release any air bubbles.
- Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 50 minutes. Cool in the pan for 10 minutes before removing to cool completely on a wire rack.