1 cup heavy cream
1/2 stick (1/4 cup) unsalted butter
2 teaspoons light corn syrup
1 pound semisweet chocolate, finely chopped
1/2 cup orange and black sprinkles, for decorating
1/2 cup orange and black sanding sugar, for decorating
Bring cream, butter, and corn syrup to a boil in a saucepan. Remove from heat. Add chocolate, and gently swirl pan to cover chocolate with cream.
Slowly whisk until smooth. Transfer to a large bowl. Cover, and refrigerate. Stir mixture every 15 minutes. After 45 minutes, mixture will thicken quickly, so stir every 3 to 5 minutes until set but still pliable, 10 to 20 minutes more (total chilling time is 55 to 65 minutes.)
Refrigerate until firm but not hard, about 10 minutes. Remove from refrigerator, and roll balls in palms to smooth. Refrigerate, in an airtight container, layered between pieces of parchment or waxed paper, until ready to decorate.
Remove balls from refrigerator. Place sprinkles and sanding sugar in separate small bowls. Dip balls into sprinkles or sanding sugar to coat, pressing sprinkles to adhere. Truffles can be refrigerated in an airtight container for up to 1 week.