Rocky Road Crunch Bars - Nigella Lawson

From Nigella Lawson's "Nigella Express"

• Ready In: 15 mins
• Serves: 24
• Yields: 24 bars

Ingredients

• 10  ounces  semisweet chocolate
• 9  tablespoons unsalted butter, softened
• 3  tablespoons golden syrup or 1⁄4 cup corn syrup
• 8  ounces  digestive biscuits (or other hard, plain cookie) or 8  ounces  ginger snaps (or other hard, plain cookie)
• 2  cups mini marshmallows
• 2  tablespoons powdered sugar

Directions

1. Melt chocolate, butter and golden syrup together over low heat.
2. Put digestive biscuits in a ziptop bag. Bash with a rolling pin until you have a mixture of coarse and fine crumbs.
3. Remove 1/2 cup of the melted chocolate mixture and set aside. Add biscuit crumbs and marshmallows to the chocolate remaining in the pan. Mix thoroughly. Turn out into a 9" square pan. Pat out flat. Drizzle reserved chocolate over the top.
4. Refrigerate several hours or overnight. Dust top with powdered sugar and cut into 24 bars.