To make this Basque cream cake, we’ll start by preparing the dough, which will then rest in the refrigerator overnight…
Make a syrup with the star anise: steep them in a 1:1 syrup (half sugar, half water), or use two tbsp of Pastis.
Place the softened butter and sugar in a bowl, then beat them together using an electric mixer fitted with the cake-mixing whisk attachment.
Add the almond flour and powdered sugar at the same time, and continue beating the mixture.
Add the egg and the egg yolks, and continue beating.
Add the flour and baking powder, and continue beating.
Finally, add the bitter almonds and the star anise-infused syrup (or two tbsp of pastis). Then mix until fully combined. Let the dough rest in the refrigerator.
Second night
Place the one and a half sheets of gelatin in a bowl with cold water. Bring the milk to a boil with a vanilla bean (over very low heat).
Meanwhile, beat the sugar, egg whites, and whole egg until light and fluffy.
Next, gradually add the flour to the mixture. When the milk begins to boil, remove it from the heat. Pour half of the milk into the egg-sugar-flour mixture while stirring. Return the mixture to the saucepan containing the remaining half of the milk, stir, and return it to the heat.
Stir until the cream thickens. Remove from heat at that point.
Drain the cold water from the bowl containing the gelatin and add a tbsp of hot water to dissolve the gelatin. Mix well , then pour into the pastry cream along with the rum. Mix again. The pastry cream is ready; set it aside in the refrigerator, covered with plastic wrap to keep it from drying out.
Final step: assembling the cake
Preheat the oven to 170°C. Remove the dough from the refrigerator. Divide the dough into two roughly equal pieces. Roll out each piece between two sheets of parchment paper until the dough is about 3/4 mm thick.
Whisk an egg yolk with a tbsp of water to use as an egg wash for the cake. Place the first piece in the springform pan, making sure the sides rise about 3 cm above the bottom, if possible.
Next, remove the top sheet of parchment paper and trim the bottom sheet as neatly as possible. Use the leftover dough (shaping it into long strips) to smooth out the edges and create a neat border.
Apply the glaze to the bottom of the cake.
Pour the cream into the bottom of the cake.
Remove a sheet from the second piece of rolled-out pastry, then cover the cake with it. Remove the second sheet (the top one), then trim off any overhanging edges and seal the two pieces of rolled-out pastry around the filling by pinching them together.
Use the remaining dough to roll out and shape decorative figures to place on top of the Basque cake (such as a clover, for example).
Brush the top with egg yolk mixed with water as well. The cake is ready to go in the oven for about 30 minutes. But feel free to check it and bake it a little longer if there are still any pale spots.
Let the cake cool to room temperature (don't put it in the fridge). You'll be able to enjoy the fruits of your labor tomorrow!