Start by peeling the banana and chopping it into round slices.
In a skillet, add the unsalted butter and stir until fully melted.
Add the condensed milk and stir for another minute.
Next, add the banana slices, turn down the heat and let them cook for 5 minutes.
Meanwhile, put the egg in the bowl and beat until foamy.
Add the milk, another 100g of condensed milk and the vanilla essence, mix well until incorporated.
Add the wheat flour and the baking powder, mix gently.
Finally, add the zest and the juice of the lemon, mix until combined.
Now, transfer this batter to the skillet with the banana slices and spread it all over them.
Cover the skillet and let it cook for 7 minutes.
After this indicated time, flip, cover the skillet again and let it cook for another 7 minutes.
Transfer the cake to a nice serving plate, top it with the whipped cream and spread.
Serve.