Preheat your oven to 350°F (175°C). Gather your ingredients and tools.

In a large mixing bowl, combine all-purpose flour, granulated sugar, brown sugar, baking powder, and salt. Whisk for about 1 minute.

Slowly pour in the melted butter, milk, and vanilla extract. Stir until just combined.

Grease a 9x13 inch baking dish with non-stick spray or butter.

Pour the batter evenly into the greased baking dish and smooth the surface.

Arrange the sliced bananas on top of the batter, allowing them to slightly overlap.

Mix ground cinnamon and nutmeg in a small bowl, then sprinkle over the banana layer.

Bake for 45-50 minutes until golden brown and a toothpick comes out clean.

Allow to cool for about 10 minutes before serving.