Beat the softened butter and sugar together. Beat in the eggs one at a time. Add the vanilla and lemon juice and continue mixing. Fold in the sour cream and the mashed bananas.
Add the flour, baking powder, baking soda and salt and stir until combined.
Bake in a preheated oven at 350 degrees F (175 degrees C) for 60 minutes, or until a toothpick inserted into the center of the loaf comes out clean.
Cool the banana bread in the pan for 10 minutes before removing to a wire rack to cool completely.