1/2 oz. Creme de Cassis
6 oz sparkling wine-any will do but I prefer dryer champagne styles or CAVA to the sweeter Proseccos
pour Creme de Cassis into a champagne flute
top off with 6 oz of sparkling wine.
You will know you have correct proportions when the cocktail takes on a mild dusty rose hue. Of course, always feel free to adjust proportions to your own taste.