8oz/230 g(1 and 1/3 cups) chopped bittersweet or semi-sweet chocolate
½cup(1 stick/115 g) unsalted butter
1and ½ cups miniature marshmallows(if you only have large marshmallows, cut them into small pieces)
¾cup(75 g) hazelnuts (or use your favorite - salted peanuts, walnuts, almonds, pecans)
¾cup(75 g) digestive biscuits or cookies (any kind)
Line an 8x8-inch baking pan with foil or parchment paper. Set aside.
In a medium heatproof bowl, combine chocolate and butter. Heat in the microwave for 30 seconds. Heat more, at 20-second intervals, stirring in between each interval, until melted. Stir in vanilla extract. Fold in marshmallows, nuts, and cookies.
Spread mixture into prepared pan. Refrigerate for at least 2 hours, or until set. Lift from pan using the foil or parchment paper, and cut into squares. Keep in the fridge. I like to take it out of the fridge 15 minutes before serving.