Sift together flour, sugar, baking soda, baking powder, and salt. Set aside.
Whisk together egg, buttermilk, milk, and melted butter in separate bowl. Stir flour mixture into milk mixture until flour just disappears; do not over mix.
Spray non-stick skillet lightly with cooking spray. Heat over medium heat. Ladle about 1/4 cup of batter into the pan for each pancake. Immediately press 4 or 5 banana slices into each so the batter oozes slightly over the fruit. Cook until bubbles appear and then flip and cook on other side, about 3 minutes total. A good tip to keep your batches warm is to heat the oven to 200. Transfer platter of cooked pancakes to oven while you cook remaining batches. Serve warm with syrup.