Put the water and fine sugar in a pot and cook until a thick syrup forms. Break the egg whites into a bowl and whip them until stiff foam. Add the sugar slowly to the egg whites, whipping constantly until the mass is smooth and shiny. Add the powdered sugar and almond flour slowly into it, gently stirring. When the ingredients blend ideally, add a few drops of purple food colouring. Put the pastry into a pastry bag and squeeze small circles onto a silicon mat. Put the mat with the pastry over onto a baking tray and knock it gently against the table top to let the air out of the pastry. Leave the macaroons at room temperature for 40 minutes and then put them into a heated oven and bake at 150°C for 15 minutes. Take the ready macaroons out to cool down.
Put the melted chocolate, mascarpone and blueberries into a bowl and mix until the ingredients blend into an ideally smooth mass. Put the cream into a refrigerator for a while to thicken. You can adjust the thickness of the cream by adding more melted chocolate to it.
Put the cream over into the pastry bag and place a small amount of cream on the pastry, covering it with the second piece of pastry.