In the 4 1/2-quart bowl of a heavy-duty electric mixer using the
paddle attachment, beat the cream cheese at low speed for 30 to 45
seconds, until creamy. Gradually add the sugar in a steady stream and
beat at medium speed until blended. At low speed, one at a time, add
the eggs, beating well after each addition. Slowly beat in the
reserved 2 cups of chocolate ganache. Beat in the cornstarch mixture.
Pour the filling into the prepared pan and, using a rubber spatula,
smooth the top.
Bake the cheesecake for 1 hour and 15 minutes to 1 hour and 20
minutes,
or until the center is set. (There will probably be cracks in the
top of
the cheesecake; they will shrink as the cheesecake cools and then
will
be covered with the ganache frosting.) Turn off the oven. Prop
open the
oven door with a wooden spoon and allow the cheesecake to cool in
the
oven for an hour.
Set the cheesecake in the pan on a wire rack and cool completely.
Make the chocolate truffles:
Transfer the chilled 1 cup ganache to a pastry bag fitted with a
1/2-inch plain tip (such as Ateco #6). Pipe l-inch mounds with
pointed
peaks onto a clean baking sheet. Refrigerate or freeze the
truffles for
15 to 20 minutes, or until just firm enough to roll.
Sift a light dusting of confectioners' sugar over the truffles.
Lightly
coat your palms and fingertips with confectioners' sugar. With
your
fingertips, pinch a truffle into a round, then roll it gently
between
your palms into a round ball. Place the truffle on the baking
sheet, and
form the remaining truffles into rounds. Refrigerate or freeze for
about
10 minutes, just until firm.
Roll the truffles in sifted cocoa powder to coat. Refrigerate.
Decorate the cheesecake:
Run a thin-bladed knife around the edge of the cheesecake to
loosen it
from the side of the springform pan. Remove the side of the pan.
Slide
two metal cake spatulas under the cheesecake and transfer it to a
serving platter.
Using a metal cake spatula, spread the reserved room-temperature
chocolate ganache evenly over the top and sides of the cheesecake.
Place
the chocolate truffles around the outside edge of the top of the
cheesecake, spacing them evenly.
Melt the white chocolate according to the instructions in the
Chocolate Key. Using a fork, drizzle/shake the warm white
chocolate in a decorative zigzag pattern over the top of the
cheesecake.
Refrigerate the cheesecake for at least 6 hours, or overnight,
before
serving. (The cheesecake can be prepared ahead and refrigerated
for up
to 5 days.)
Remove the cheesecake from the refrigerator 30 minutes before
serving.
With a sharp, thin-bladed knife, cut the cheesecake into 12
truffle-topped slices, dipping the blade in hot water and wiping
it dry
after each slice.
