In a small saucepan, bring the heavy cream to a boil

over medium-high heat. Put the chocolate chips in a

heatproof medium bowl and pour the boiling cream over

the chocolate. Let sit until the chocolate is melted,

about 2 minutes. Stir the mixture with a fork for

about 2 minutes, until the ganache is smooth.

Line a nonstick 9 x 5 x 3 3/4-inch loaf pan with 2

overlapping sheets of plastic wrap, allowing a 4-inch

overhang on all sides.

Pour half of the ganache (1 cup) evenly into the lined

pan and spread to cover the base. Cover the ganache

with a single layer of tightly packed cake slices; be

sure the layer is flat and even. Working quickly,

spread the vanilla ice cream evenly over the pound

cake.

Cover the ice cream with a layer made of half of the

chocolate wafers. Spread the remaining ganache evenly

over the wafers, then top the ganache with another

layer, using all of the remaining wafers, and place

the cake in the freezer for about 30 minutes to chill

and firm up.

Remove the cake from the freezer and spread the

chocolate ice cream over the wafers. Top with another

flat, single layer of tightly packed slices of pound

cake, trimming 1 or 2 slices to fill in the gaps

(there will be a few slices left over). The cake may

be slightly higher than the pan. Cover the cake

completely with the plastic overhang and freeze until

firm, at least 5 hours or overnight.

To loosen the ice cream cake from the pan, open the

plastic wrap and invert the pan over a flat serving

platter. Remove the plastic wrap. Scatter the crushed

chocolate wafers over the ice cream cake, then slice

and serve immediately.