Chocolate, Chestnut and Orange Trifle

INGREDIENTS

Orange, large

chocolate bar

1 cup

Sugar

1 15 ounce can

Chestnut puree * see cook's note

frozen pound cake, thawed, cut into 1/4 to 1/2-inch thick slices, frozen

1 cup

Orange juice

2 tbsp

Butter, unsalted

3 cups

Heavy cream

3/4 cup

Orange liqueur

8 ounces bittersweet (60 percent cacao) chocolate, broken into 1/2-inch pieces