Praline: Roast the nuts at 300°F (150°C) for 15 minutes, then let cool.

Cook sugar and water until caramelized and brown, then add nuts. Stir quickly until well mixed, then transfer to a heat-resistant surface (parchment paper/silicone mat), spread out, and let harden and cool. Once cool, break into small pieces for easy grinding.

Blend the praline into a smooth and creamy paste (I use a food processor). Cool.

Praline Mousseline Cream: Whisk egg yolks and sugar with a balloon whisk until pale. Add flour and cornstarch, temper with the heated milk and cream mixture, then cook again while stirring until boiling. Add vanilla extract, turn off the heat, add butter, and stir until well combined. Cool in the fridge.

Choux Pastry: Combine milk, water, and butter, bring to a boil, then turn off the heat. Add flour, stir until well mixed, cook again on low heat until a thin crust forms on the bottom of the pan. Let cool.

Gradually add eggs, stirring until smooth (I use a hand mixer on low speed, but a spatula can also be used). Transfer to a piping bag and pipe into a circle (I use a 20 cm diameter).

Sprinkle the surface with powdered sugar and sliced almonds, then bake at 365°F (185°C) until golden brown (35-40 minutes). Cool.

Cut the choux pastry, then fill with cream using a piping tip. Stack to form a mound of cream, then cover with the other half of the pastry. Here, I spread the bottom of the choux with leftover praline; this step is optional and can be skipped.