Chocolate Truffle Tart
For crust
28 chocolate wafers such as Nabisco Famous (not oreos),
finely ground in a food processor (1 1/2 cups)
3/4
stick (6 tablespoons) unsalted butter, melted and cooled completely
For filling
1/2 lb fine-quality bittersweet chocolate (no more than 60% cacao if marked), coarsely chopped
(I used Ghirardelli 60% chocolate chips)
3/4 stick
stick (6 tablespoons) unsalted butter, cut into 1/2-inch cubes
2
large eggs, lightly beaten
1/3
cup
heavy cream
1/4
cup
granulated sugar
1/4
teaspoon
salt
1
teaspoon
pure vanilla extract
Garnish
unsweetened cocoa powder for sprinklingMake crust:
Put oven rack in middle position and preheat oven to 350°F. Wrap a sheet of foil over bottom of springform pan (in case of leaks). Lightly butter side of pan. You can also use a tart pan, which is what I did. I did not worry about buttering the pan and it turned out great.
Stir
together ground wafers and butter in a bowl until combined, then pat
mixture evenly onto bottom of pan and 1 1/2 inches up side. Bake until
crust is slightly puffed, about 10 minutes, then cool completely in pan
on a rack, about 15 minutes. Leave oven on.
Make filling while crust cools:
Melt chocolate and butter in a 2-quart heavy saucepan over low heat, stirring until smooth, then remove from heat and cool 5 minutes.
Whisk together eggs, cream, sugar, salt, and vanilla in a bowl. Whisk chocolate mixture into egg mixture until combined well.
Assemble and bake tart:
Pour filling into cooled crust and rap pan once on counter to eliminate any air bubbles. Bake until filling 1 inch from edge is set and slightly puffed but center trembles slightly when pan is gently shaken, 20 to 25 minutes. (Center will continue to set as it cools.)
Cool tart
completely in pan on a rack, about 2 hours. Chill, uncovered, until
center is firm, about 4 hours. Remove side of pan and sprinkle with
cocoa to serve.