Thomas Keller's Chocolate Bouchons (Bouchons au Chocolate)

1 . Stage

Preheat the oven to 350 degrees F.

2 . Stage

Butter and flour 12 timbale molds (Bouchon Bakery uses 2-ounce Fleximolds and serves smaller bouchons. You can also use 3-ounce [2- to 2 1/2-inch diameter] timbale molds for larger cakes.) Set aside.

3 . Stage

Sift the flour, cocoa powder, and salt into a bowl; set aside. In a large bowl, mix together the eggs and sugar on medium speed for about 3 minutes, or until very pale in color. Mix in the vanilla. On low speed, add about one-third of the dry ingredients, then one-third of the butter, and continue alternating with the remaining flour and butter. Add the chocolate and mix to combine. (The batter can be refrigerated for up to a day.)

4 . Stage

Put the timbale molds on a baking sheet. Place the batter in a pastry bag without a tip, and fill each mold about two-thirds full. Place in the oven and bake for 20 to 25 minutes. When the tops look shiny and set (like a brownie), test one cake with a toothpick: It should come out clean but not dry (there may be some melted chocolate from the chopped chocolate). Transfer the bouchons to a cooling rack. After a couple of minutes, invert the timbale molds and let the bouchons cool upside down in the molds; then lift off the molds.

5 . Stage

To serve, invert the bouchons and dust them with confectioners' sugar. Serve with ice cream if desired. (The bouchons are best eaten the day they are baked.)