In a small saucepan, combine fresh or frozen black raspberries with sugar and water over medium-low heat. Cook for about 10 minutes until the berries soften and sugar dissolves.

Transfer the cooked berry mixture into a blender, and blend until smooth for about 30 seconds.

Using a fine mesh sieve, strain the blended berry mixture into a bowl or jar to remove seeds and pulp.

In a tall glass, add a couple of tablespoons of your homemade black raspberry syrup. Fill the glass halfway with crushed ice.

Pour in plain sparkling water or club soda, filling the glass to the brim. Add a splash of heavy cream on top.

Gently stir the drink before serving to blend the flavors. Garnish with fresh raspberries or mint if desired.