Melt-in-your-mouth cake, simple and inexpensive

Icing sugar

For the dough:

125 g butter
1 tbsp baking powder (optional)
25 cl water
5 medium eggs (or 4 large eggs)
1 cup T 45 or T 55 flour (150 g)

For the cream:

250 g butter
80 cl milk
2 sachets vanilla sugar
80 g flour
2 egg yolks
3/4 cup sugar (150 g sugar)
80 g potato starch
The cake mixture melts in your mouth