Crush the chocolate creme sandwich cookies in a food processor until fine crumbs. Melt unsalted butter and combine with the cookie crumbs. Press into the bottom of serving glasses and chill for 30 minutes.

Blend softened mascarpone cheese, chocolate hazelnut spread, powdered sugar, and vanilla extract in a stand mixer until smooth. Whip heavy cream to soft peaks and fold into the mascarpone mixture.

Spoon the creamy filling over the chilled cookie crusts. Smooth the tops and cover with plastic wrap. Refrigerate for at least 2 hours or overnight.

Whip extra heavy cream to soft peaks for garnishing. Spoon on top of each cup and add toppings like chocolate curls or crushed hazelnuts before serving.