In a medium saucepan, melt 80 grams of butter with 100 ml of milk, 100 ml of water, and ½ teaspoon of salt over medium heat. Stir continuously until the mixture reaches a boil.

Once boiling, quickly blend in 150 grams of all-purpose flour and 1 teaspoon of baking powder using a wooden spoon, mixing until a smooth dough ball forms.

Remove the saucepan from heat and allow the dough to cool for about 10 minutes. Once it’s warm but not hot, gradually add 4 whisked eggs, mixing well after each addition until the dough is smooth and shiny.

Preheat your oven to 400°F (200°C). Divide the dough into two equal parts, and transfer each part into a lined round baking pan. Bake both layers for about 20 minutes or until they turn a lovely golden brown.

While the cake layers cool, prepare the cream filling. In a mixing bowl, beat together 100 grams of sugar and 4 eggs until frothy. Gradually incorporate 30 grams of flour and 100 ml of milk.

Then, pour the mixture into a saucepan over medium heat, stirring constantly until it thickens to a custard-like consistency, approximately 5-7 minutes. Remove from heat and cover to cool.

Once the cream filling is cool, you can whip 80 grams of butter in a bowl until it becomes fluffy and pale, about 3-4 minutes.

Gradually mix in the cooled cream filling until you achieve a smooth, creamy consistency.

To assemble your Melt-in-Your-Mouth Cake, place one cooled cake layer in a serving pan. Spread half of the creamy filling evenly over the layer.

Gently place the second cake layer on top and finish with the remaining cream filling, smoothing it out beautifully. Refrigerate the assembled cake for at least 2 hours to allow it to set.

Before serving, dust the top of your Melt-in-Your-Mouth Cake with powdered sugar for a sweet finishing touch.