Chocolate Hazelnut Crunch Truffles

Bahan-bahan (40 porsi)

• 16 ounces (450g) semi-sweet or milk chocolate, coarsely chopped and divided*
• 1/2 cup (120ml) heavy cream
• 1/3 cup (100g) Nutella
• 2 Tablespoons (28g) unsalted butter, softened to room temperature
• 3/4 cup (90g) toasted and finely chopped hazelnuts, divided*