01 - Preheat the oven to 350°F. Grease an 8-inch square baking dish.
02 - In a large skillet, melt 2 tbsp butter over medium heat. Add sliced bananas, granulated sugar, brown sugar, cinnamon, nutmeg, vanilla extract, lemon juice, and salt. Cook for 3–5 minutes, stirring gently, until bananas are softened and the mixture is saucy. Remove from heat.
03 - Spread the banana mixture evenly into the prepared baking dish.
04 - Whisk together flour, sugar, baking powder, and salt. Add milk, melted butter, and vanilla. Stir until just combined.
05 - Spoon the batter over the bananas. Gently spread with a spatula, leaving some areas exposed.
06 - Bake for 35–40 minutes until the topping is golden brown and a toothpick comes out clean.
07 - Let cool for 10–15 minutes. Serve warm with ice cream or whipped cream.