Paris Brest!

For the filling, bring the milk to a simmer, and, while it's heating, mix the eggs and the cornstarch. Then, poor half of the hot milk on the eggs, whisk well and poor your mixture back in your saucepan. Keep on mixing until you get a thick consistency. Turn off the heat, add the butter and the praline powder, and whisk to get an aerial texture. Then, let your filling rest in the fridge, and let's make the choux pastry!

For the choux pastry, start by preheating your oven to at 210°C. Bring the water and the butter to a boil, and then add the salt and the flour. Work this dough-to-be until it's dry, remove your saucepan from the heat, and add the eggs one by one while mixing. You should now get a sticky and shiny choux pastry! You did the hardest part. Put your choux pastry in a piping bag, and make small crowns (ideally, they should be 2cm high and have a 8cm diameter) on a baking sheet. Bake 15 minutes at 210°C, then 10 minutes at 180°C. Let your crowns cool down to room temperature, and slice them horizontally. Finally, add your filling with a piping bag, sprinkle with icing sugar, and you're done, congratulations!