In a mixing bowl, whisk together the flour, sugar, baking powder, and salt until well combined.
In a separate bowl, combine the milk, egg, and melted butter. Mix well to create a wet mixture.
Pour the wet ingredients into the dry ingredients and gently fold until just combined. Be careful not to overmix; a few lumps are okay.
Preheat a non-stick skillet or griddle over medium heat. Grease lightly with a bit of butter or oil.
In another skillet, melt 1 tablespoon of butter over medium heat. Once melted, add the sliced bananas and sprinkle the brown sugar over them. Cook for about 2-3 minutes, gently flipping the bananas until they are soft and caramelized. Remove from heat and set aside.
Pour about 1/4 cup of pancake batter onto the hot skillet for each pancake. Cook for 2-3 minutes until bubbles form on the surface.
Carefully flip the pancake and cook for an additional 1-2 minutes until golden brown and cooked through.
As each pancake finishes, layer a few pieces of caramelized banana on top.
Repeat with the remaining batter and bananas until all pancakes are cooked.
Serve warm with maple syrup drizzled over the top and sprinkle with walnuts or pecans if desired.