St. Honore Cake (Classic French Gateau)

Instructions

1. Heat the oven to 400 F (200 C). Roll the puff pastry into a 9-inch (23 cm) circle, prick all over with a fork, place on a lined sheet and chill.
2. For the choux, bring the water, butter and salt to a boil, add the flour all at once and stir over medium heat 2 minutes until it forms a ball and leaves a film on the pan. Cool 5 minutes, then beat in the eggs a little at a time until smooth and glossy.
3. Pipe a ring of choux around the edge of the pastry disc, then pipe about 14 small puffs 1 inch (2.5 cm) wide on a second lined sheet. Brush the puffs and ring with yolk.
4. Bake the disc 20 to 25 minutes and the puffs 20 minutes, until deep golden and dry. Cool on racks.
5. For the cream, whisk the yolks, sugar and cornstarch. Heat the milk to steaming, whisk into the yolks, return to the pan and cook, stirring constantly, until it thickens and bubbles for 1 minute (at least 160 F / 71 C). Add the vanilla, chill with plastic on the surface, then fold in the whipped cream.
6. Poke a small hole in the bottom of each puff and pipe in the cream.
7. For the caramel, boil the sugar and water without stirring until it turns light amber, about 340 F (170 C). Dip the top of each puff and press it onto the choux ring, using a bit of caramel as glue.
8. Pipe the remaining cream in the center. Chill up to 3 hours and serve the same day.