When is chocolate ever too much. No cooking required here:
Ingredients
125 ml (½ cup) milk
150 g mini marshmallows
150 g dark chocolate (70 per cent cocoa solids)
300 g Tim Tams or other chocolate coated-cream-filled biscuits
70 g cold unsalted butter, chopped
pinch of salt
300 ml thickened cream

Instructions
Chilling time: 5 hours
1. Lightly grease a 22-23 cm tart tin with removable base. Line the base with baking paper.
2. Place the milk, marshmallows and chocolate in a saucepan over medium-low heat. Cook, stirring occasionally until the marshmallows have melted. Remove from the heat and stir until mixture is thick, silky and smooth. Set aside to cool to room temperature.
3. Meanwhile, place the chocolate biscuits, chopped butter and salt in a food processor and process until it starts to break down into a wet-sand-like consistency and clump together.
4. Tip the crumb mixture into the lined tin and press into the base and sides with your fingers to form an even tart shell. You want to make sure that the edge is at least 5 mm thick. Refrigerate while you finish the filling.
5. Using an electric stand mixer, whisk the cream until soft peaks form. Gradually whisk in the cooled marshmallow mixture until smooth and well combined. Pour the filling into the tart shell and spread it evenly. Refrigerate for at least 5 hours or until set.