Line a 8x8 baking pan with greaseproof or parchment paper and set aside.
Place the chocolate, butter and golden syrup into a medium heavy-based saucepan. Heat over a low heat, stirring frequently, until fully melted. Take care not to overheat this - it should only be warm, not hot. I usually remove the pan from the heat before everything is melted and let it continue to melt in the residual heat.
10 ounces dark chocolate (60-70% cocoa solids), ½ cup salted butter, 3 tablespoons golden syrup
Place the ginger nuts into a large freezer bag and bash them with a rolling pin until you have a chunky rubble - ensure you have some large pieces as well as crumbs.
7 ounces ginger nuts/ginger snaps
Stir the ginger nuts into the just warm chocolate mixture, followed by the mini marshmallows, dried cranberries, chopped pistachios and orange zest. Mix well.
2 cups mini marshmallows, ½ cup dried cranberries, ⅓ cup chopped pistachios, zest of 1 orange
Pour the rocky road mixture into the prepared pan and place in the fridge whilst you get the topping ready.
Place the white chocolate into a small heatproof bowl and place over a pan of simmering water. Stir occasionally until melted.
7 ounces white chocolate
In another small bowl, place the dark chocolate and set over a pan of simmering water. Stir occasionally until melted.
1 ounce dark chocolate
Remove the rocky road from the fridge. Pour the white chocolate over the top and working quickly with a spatula, spread it out over the top of the rocky road. You might get a few streaks of dark chocolate showing through but don't worry as you're going to pour more dark chocolate on top.
Drizzle the dark chocolate in lines going in one direction over the top of the white chocolate. Run a toothpick/cocktail stick through the dark chocolate in the opposite direction to your lines to swirl the dark chocolate into the white.
Sprinkle a few extra dried cranberries and chopped pistachios over the top. Place in the fridge to set for at least 4 hours.
When set, grab the edges of the parchment paper and pull the rocky road out of the baking pan. Cut into 16-25 squares and enjoy!