Into a bowl, start by adding the oats and the hot milk, mix very well and set aside.
Into another bowl, add the banana chopped into round slices, mash them well.
Add the egg, the cocoa powder, the baking powder, mix all the ingredients very well and add the milk-oats mixture, mix all the ingredients very well again.
Once you’ve done that, into a baking dish, add 1 drizzle of vegetable oil and spread well.
Pour in the batter we made.
Bake in a preheated oven at 180°C (356°F) for 30 minutes, baking time may vary depending on the power of your oven.
Meanwhile, melt the semisweet chocolate and add the table cream, mix until combined.
Once the cake has baked through, pour the ganache all over it.
Take it to the fridge and let it chill for at least 1 hour.
Serve.