Hot Chocolate Nanaimo Bars

• 1/2 cup unsalted butter, cut in pieces
• 1/4 cup granulated sugar
• 1/4 cup cocoa powder
• 1/2 tsp salt
• 1 large egg, lightly beaten
• 1 1/2 cups graham cracker crumbs
• 1 cup sweetened flaked coconut or toasted sliced almonds

• 1/2 cup unsalted butter, room temperature
• 1 1/2 cups icing sugar, sifted, divided
• 1/3 cup powdered hot chocolate mix
• 2 tsp vanilla custard powder
• Pinch fine salt
• 3 tbsp 1% or 2% milk

• 4 oz couveurure/baking chocolate, chopped
• 2 tbsp unsalted butter
• 1 1/2 cups mini marshmallows
• Sea salt for sprinkling, optional

Method...

1. Lightly grease a 9-inch (23 cm) square pan. Line with parchment paper so that it comes up the sides.
2. For the crust, place the butter, sugar, cocoa powder and salt in a metal bowl and set over a pot of gently simmering water, whisk-ing until the butter has melted. Add the lightly beaten egg and whisk until the mixture thickens to the consistency of pudding, about 1 minute. Remove the bowl from the heat and stir in the graham cracker crumbs and coconut (or almonds). Scrape the crust mixture into the pan and spread to level it. Chill the pan while preparing the filling.
3. For the filling, beat the butter with 1 cup (130 g) icing sugar until smooth. Stir the hot chocolate mix, custard powder and salt with the milk (it will make a thick paste) and stir into the butter mixture until smooth. Beat in the remaining ½ cup (65 g) icing sugar. Do not overbeat—the filling should be smooth but not fluffy. Spread evenly over the crust (no need to refrigerate).
4. For the topping, melt the chocolate and butter in a metal bowl placed over a pot of barely simmering water, stirring gently with a spatula until melted. Cool the chocolate slightly and then pour over the filling, spreading to cover it. Sprinkle the marshmallows on top of the chocolate in an even layer (it will not fully hide the chocolate)and,if you like, finish with a sprinkle of sea salt.
5. Chill the pan for about 2 hours before slicing into bars. Nanaimo bars will keep in an airtight container in the fridge for up to 1week.

Makes 18 bars (one 9-inch pan)