Preheat the oven to 350F.

Place the bananas in a bowl and add the sugar, salt, ground cinnamon, chocolate and ground nutmeg. Set aside.

For the topping: Combine the flour, sugar, brown sugar, oatmeal and butter in a bowl. Mix well until well combined.

Pour the banana mixture in the baking dish. Sprinkle the topping evenly over the bananas.

Bake until the topping is crisp and golden brown and the banana-chocolate filling bubbles slowly, about 45 minutes. Serve warm.