"Create a recipe for Brown Butter Espresso Cookie Sandwiches using all the original ingredients provided: 115g unsalted butter (to be browned), 100g light brown sugar, 50g caster sugar, 1 large egg, 1 teaspoon vanilla extract, 1 tablespoon honey, 150g plain flour, 100g rolled oats, 2 tablespoons instant espresso powder, 1/2 teaspoon ground cinnamon, 1/2 teaspoon bicarbonate of soda, 1/2 teaspoon fine sea salt, 75g hazelnuts toasted and chopped; and for the espresso cream filling: 75g unsalted butter softened, 200g icing sugar, 1 tablespoon instant espresso powder, 1/2 teaspoon vanilla extract, 1-2 tablespoons double cream as needed. Ensure the quantities are balanced and the recipe is beginner-friendly with UK spelling and metric units."