Prepare the Bowl and Line with Cake:

Cup of Yum
1. Line a 2 ½ quart bowl with plastic wrap. Have it much larger than you need to cover the top later.
2. Cut the sponge cake in half. I love using a cake slicer.
3. Place one slice in the bottom of the bowl. If you're using a loaf cake, cut slices and then triangles and fill the bowl like a jigsaw puzzle to cover every spot, so that the entire bowl is covered.
4. Slice a few pieces of the other half of the cake into strips.
5. Use the strips to line around the cake in the bowl. This only takes a few minutes, and its very easy!
6. Sprinkle the cake with your choice of liqueur. I used Kahlua this time.

Make the Pastry Cream:

1. In a medium sized pot (off the heat), stir the egg yolks and sugar together briskly with a wooden spoon. 
2. Add the flour a little at a time and incorporate into the mixture.
3. Heat the milk to boiling and add the vanilla. Begin adding the hot milk to the mixture a little at a time, mixing well in between additions. Do not add too much at once or the eggs may curdle.
4. Continue adding the hot milk and stirring continuously with a wooden spoon.
5. Once all the milk has been added, put the pot onto medium heat and continue to stir.
6. When the mixture comes to a boil, let it cook for 3 or 4 minutes then remove from the heat. Keep stirring as it cools so that it doesn't form a skin.

Melt the Chocolate:

1. Melt the chocolate in the microwave, or in a bowl over some hot water.
2. Set aside.

Make the Zuccotto Filling:

1. In a medium sized bowl, beat 10 oz (300 ml) heavy whipping cream with the instant coffee powder until stiff peaks form; set aside.
2. To the cooled pastry cream, add 1 Tbsp of Grand Marnier, the 2 oz (55 g) of grated chocolate and the whipped coffee cream. Fold mixture until completely combined.
3. Spread ⅔ of the mixture into the cake-lined bowl almost reaching the top, but not completely. Leave a hollow in the middle and don't worry if it doesn't look perfect, it will be fine in the end.

Fill the Zuccotto:

1. Add the melted chocolate to the remaining cream.
2. Mix well until the color is uniform, then fill the center of the zuccotto.

Seal the Zuccotto and Chill:

1. Take pieces of the remaining cake and close up the bottom of the zuccotto. 
2. Sprinkle with more of your chosen liqueur, then seal with plastic wrap and refrigerate for at least 6 hours, but I like to leave it overnight.

Decorate the Zuccotto:

1. Beat the remaining 8 oz (235 ml) of heavy whipping cream, with the other 2 teaspoons of coffee powder and 2 tablespoonfuls of sugar until stiff peaks form.
2. When ready to decorate, remove top plastic wrap and place a FLAT plate or cake stand on top of the zuccotto and invert. Remove the bowl.
3. Ta dah! This is my favorite part! Have cracks? Doesn't matter, it's still going to turn out perfectly.
4. Spread the coffee-flavored whipped cream all over the zuccotto.
5. Make swirls or peaks in the cream, whichever way you like, but it doesn't have to be fancy.  Sprinkle with chocolate shavings, curls or more grated chocolate.
6. It's best to refrigerate the cake for an hour or so. However,  you can serve it immediately if you need to.