Preheat the oven to 375F. Use 1 tablespoon of the coconut oil to grease an 8-inch or equivalent baking dish.
Spread the banana slices across the bottom. Slice the remaining fruit. Scatter about 2/3 of the fruit on top of the bananas, reserving the rest for the top.
In a bowl, combine the oats, flaked coconut, baking powder, and salt. Sprinkle the dry mixture over the fruit in the baking dish.
In a bowl, whisk together the maple syrup, coconut milk, egg, remaining 2 tablespoons of coconut oil, and vanilla. Drizzle the wet mixture over the oats.
Arrange the remaining fruit slices over the top.
Bake for 35-45 minutes, until the top is golden and the oats are set. Let cool for a few minutes.