In a small saucepan, combine blackberries and water. Cook over medium heat for about 5 minutes until berries soften and release their juices.
Mash the berries gently and add sugar or honey if using. Stir until dissolved.
Strain the mixture through a fine mesh strainer to remove seeds. Let the puree cool.
Add 1 to 2 tablespoons of blackberry puree to a champagne flute.
Slowly top with chilled prosecco or champagne.
Gently stir once and garnish if desired. Serve immediately.
Notes
Tips for the Best Blackberry Mimosa
Always chill your sparkling wine thoroughly before serving to keep the drink crisp. Use fresh blackberries when in season for the best flavor, but frozen berries work perfectly year-round. Start with less puree and add more as needed so the mimosa does not become overly sweet or heavy. Pour the sparkling wine slowly to preserve the bubbles and prevent overflow.
Variations and Substitutions
For a Blackberry Orange Mimosa, add a splash of fresh orange juice. To make it lighter, use sparkling water mixed with prosecco. For a sweeter brunch cocktail, substitute peach nectar or raspberry puree. A non-alcoholic version works beautifully with sparkling white grape juice or club soda. You can also swap blackberries for blueberries, raspberries, or strawberries depending on what you have on hand.