01 - In a heatproof bowl, combine dark chocolate, milk chocolate, and unsalted butter. Place over a saucepan of gently simmering water, stirring continuously until melted and silky. Remove from heat and blend in heavy cream until homogeneous. Let cool slightly.
02 - Line an 8-inch square pan with parchment paper. Pour the chocolate mixture into the pan and spread evenly using a spatula.
03 - Distribute crushed pistachios, digestive biscuits, and toasted coconut flakes over the chocolate base. Gently press the toppings into the melted chocolate so they adhere.
04 - In a small saucepan, combine pitted dates, water, ground cardamom, and fine sea salt. Cook over low heat while stirring until dates soften and water is absorbed, about 5 minutes. Puree until smooth using a blender or immersion blender.
05 - Spoon or swirl the spiced date caramel across the crunch-topped chocolate base for marbled texture.
06 - Transfer the pan to the refrigerator and chill for at least 2 hours, until fully set and firm.
07 - Lift the set chocolate slab from the pan and cut into bars or squares with a sharp knife. Finish with edible gold leaf, dried rose petals, and extra chopped pistachios.