To make the crepe batter, place peeled bananas, eggs, and a pinch of salt in a blender or a food processor and blend until homogeneous. Pour half the milk into the banana mixture and beat for a few seconds. Transfer the preparation to a large bowl.

Add the sifted flour and mix with a hand whisk or an electric mixer. Finish with the rest of the milk and water and mix until no lumps. To remove lumps, if desired, pass the batter through a fine-mesh sieve. Add melted and cooled butter and let the batter rest for at least 15 minutes, better for half an hour.

Cook crepes on a well-heated crepe pan. Pour a small ladle of the batter into the center of the pan. Immediately swirl the pan in a circular motion to spread the batter into a thin layer. Let the crepe cook for 1-2 minutes on the first side.

Then, use a flexible turner to flip it over to the second side to finish cooking. The cooking time depends on the intensity of the heat (keep the medium heat or medium-low heat) as well as your taste. Place the crepe on a plate and continue with the remaining batter.

To garnish crepes, place Nutella in a microwave-safe bowl and warm it in the microwave for 20-second intervals. Stir it with a spoon: it has to be spreadable. Peel and slice bananas into pretty thin slices and sprinkle them with lemon juice to prevent darkening.

Spread Nutella (1-2 tablespoons) over half of the crepe, and arrange slices from 1/3 of the banana on top of the spread. Fold the crepe with the unfilled half of the crepe to obtain a half-moon. Then fold in half again, making a triangle shape.

Serve one or two on a dessert plate. Dust with powdered sugar or sprinkle with chopped toasted hazelnuts for extra flavor. Or make an easy Nutella drizzle if desired.