Chill your glasses: Place two champagne flutes or coupe glasses in the freezer for a few minutes while you prep. A cold glass keeps everything bubbly longer.
Combine the base: In a cocktail shaker, add gin, Chambord, lemon juice, and simple syrup.
Shake with ice: Fill the shaker with ice and shake vigorously for 15-20 seconds until very cold.
Strain: Strain evenly into your two chilled glasses.
Top with Prosecco: Slowly pour 2 oz of chilled Prosecco into each glass. Give it a very gentle stir.
Garnish: Drop a few fresh raspberries into each glass and add a lemon twist on the rim.
Serve immediately — bubbles wait for no one!