Sift together the flour, sugar, baking powder, and salt. In a separate bowl, whisk together the sour cream, milk, eggs, vanilla, and lemon zest. Add the wet ingredients to the dry ones, mixing only until combined.
Melt 1 tablespoon of butter in a large skillet over medium-low heat until it bubbles. Ladle the pancake batter into the pan to make 3 or 4 pancakes. Distribute a rounded tablespoon of bananas on each pancake. Cook for 2 to 3 minutes, until bubbles appear on top and the underside is nicely browned. Flip the pancakes and then cook for another minute until browned. Wipe out the pan with a paper towel, add more butter to the pan, and continue cooking pancakes until all the batter is used. Serve with sliced bananas, butter and maple syrup.