Chill a glass or flûte with ice, discard the ice.
Take 1 cup of strawberries, hulled and sliced, and squeeze them by hand before placing them in a colander and pounding them with a spoon.
Add 1 tablespoon of sugar and stir until you get a smooth consistency. You can adjust the sweetness by adding more sugar if desired. Your strawberry puree is ready for the Rossini cocktail.
Pour 5 cl (1 3/4 oz) strawberry puree into the bottom of the glass.
Slowly pour chilled Prosecco over the strawberry puree to fill the glass. The bubbly wine will mix with the fruity puree, creating a beautiful layered effect.
Gently stir the cocktail with a bar spoon to combine the flavors.
Garnish the Rossini cocktail with a fresh strawberry on the rim of the glass for an elegant touch.
Serve the Rossini cocktail immediately while it’s chilled and sparkling for a delightful and festive drink.