Preheat your oven to 350°F (175°C). Place a 9- or 10-inch oven-safe skillet (cast iron works best) on the stove over low heat to warm slightly.

In a mixing bowl, whisk the mashed bananas, granulated sugar, brown sugar, 6 tablespoons melted butter, egg, and vanilla until smooth and glossy.

In a separate bowl, whisk the flour, baking powder, baking soda, cinnamon, and salt. Add half of the dry mix to the wet ingredients.

Pour in the milk, then add the remaining dry ingredients. Stir gently until just combined. Do not overmix or the cake can turn dense.

Lightly butter the warm skillet or mist with baking spray. Pour in the batter and spread it evenly. If using, arrange banana slices on top.

Bake for 18–22 minutes, until the center is set and a toothpick comes out with just a few moist crumbs. The edges should be golden.

While the cake bakes, make the caramel. In a small saucepan, add brown sugar and 2 tablespoons butter over medium heat. Stir until the sugar looks wet and starts to bubble around the edges, 1–2 minutes.

Whisk in the heavy cream and a pinch of salt. Simmer for 1–2 minutes until slightly thickened. Remove from heat and stir in vanilla. The caramel will thicken as it cools.

When the cake is done, let it rest for 5 minutes. Drizzle warm caramel over the top, letting it seep into the edges. Add nuts or flaky salt if you like.

Serve warm, straight from the skillet, with ice cream on the side for extra decadence.