Paris-Brest!

Directions

1. 1
   Heat the water, butter and salt in a small saucepan until it just boils. Add the flour all at once and stir until it separates from the edges of the pan and forms a film at the bottom of the pan. Transfer the dough to the mixer bowl with paddle and mix slowly 3-5 minutes to allow further evaporation.
2. 2
   Add the eggs one at a time and fully incorporate them.
3. 3
   Pipe onto a buttered baking sheet according to size desired and bake at 200C (392 degrees F) until browned and fully risen (20-25 minutes). You may open the oven once during the baking process to release humidity from the oven, however do not open it repeatedly or the choux pastry may collapse.
4. 4
   Boil the milk with the vanilla extract. During this time, put the yolks in a bowl with the sugar and the corn starch. Whisk to combine. Bring the milk again to a boil. Carefully add the boiled milk into the egg yolk mixture, 1/3 at a time. Return the mixture to the heat and whisk to keep it moving while it heats up again. gg
5. 5
   Bring it to a boil, stirring and whisking (not to incorporate air) and after it boils at least one minute, remove it from heat. Transfer this immediately to a lined pan, covering again with plastic to ensure that a film does not develop on the surface while it cools. Cool immediately and keep refrigerated when not using. This will keep 3 days in the refrigerator but does not freeze well.
6. 6
   Make the mousseline: Whip the butter until it is light and fluffy. Incorporate the praline into the butter, whipping thoroughly to incorporate air. Incorporate the cold pastry cream, mixing just until fluffy and light, being careful not to whip it too much. If necessary, you can then stir it carefully with a spatula to eliminate some of the bubbles that may have formed. The mousseline praline is ready to load into piping bag for immediate use.
7. 7
   For the Noisettes Caramelisees: Heat the oven to 160°C (320 degrees F.) Spread the nuts out on a pan and bake for 16 minutes.
8. 8
   Put the hot nuts into a terry towel and roll them under your hands until the skins come off. Return the skinned hazelnuts to the oven, which has been turned off, to keep them warm. Conversely you can start with 2 cups of slivered almonds and skip this step.
9. 9
   Put the sugar, water, and a split vanilla bean and its paste which has been scraped in a thick-bottomed pan. Bring to a boil and bring to 118C. Remove the pan from the heat and add the hazelnuts. Stir until they are coated with sugar.
10. 10
    Return the nuts to the heat and stir over heat until the outside caramelizes. Sprinkle with fleur de sel and turn the caramel coated nuts immediately to a piece of baking paper. Remove the vanilla bean. Let cool. Crush lightly. Keep in an airtight container
11. 11
    To Assemble the Paris-Brest: 1/2 batch pate a choux 1/2 batch Creme Patissiere 125 + 180 g butter + praline 100 g noisettes pralinees as needed almonds, slivered as needed pearl sugar
12. 12
    Pipe one large and one small ring. Egg wash and sprinkle with pearl sugar and nuts, and bake in a hot oven until brown and crisp.
13. 13
    Make the creme patissiere, chill, and then use it to make the creme mousseline, by blanching the butter and praline before adding the creme patissiere.
14. 14
    Cut the larger circle of choux pastry slightly below the middle line. Powder the top with icing sugar. Start with the lower half, and fill it with about 1/3 of the creme mousseline. Sprinkle praline coated hazelnuts over the cream, and add the separately cooked ring. Pipe shell shapes over the ring of pastry, slightly overhanging the bottom pastry.
15. 15
    Cover with the powdered sugar topped ring. Serve immediately or refrigerate.