Melt ½ cup of unsalted butter in the microwave for about 30-45 seconds, then let it cool slightly.

In a food processor, combine 1 ½ cups of biscuit crumbs and ½ cup of ground hazelnuts. Blend with melted butter and a pinch of salt until it holds together.

Press the crust mixture evenly into the bottom and sides of an 8-inch tart pan. Chill in the refrigerator for at least 30 minutes.

Heat 1 cup of heavy cream in a small saucepan until it simmers. Remove from heat.

Chop 8 ounces of dark chocolate and add it to a mixing bowl with ½ cup of hazelnut butter. Pour in the hot cream and stir until blended.

Pour the ganache filling into the chilled tart shell and spread evenly with an offset spatula.

Cover loosely with plastic wrap and refrigerate for at least 4 hours to set.

Once set, remove from the pan and garnish with roasted hazelnuts before serving.