Start by rinsing your firm seedless grapes under cold water, ensuring they are thoroughly cleaned. Gently pat them dry with a clean kitchen towel or paper towel to remove excess moisture.

In a shallow dish, combine your choice of Prosecco sparkling wine and vodka. Add the cleaned grapes, ensuring they are fully submerged. Cover with plastic wrap and refrigerate for at least 8 hours, preferably overnight.

Once the soaking time is up, carefully drain the grapes, leaving them slightly damp. Roll the damp grapes in granulated sugar until well-coated.

Arrange your coated grapes on a serving tray and chill in the refrigerator for an additional 2 hours before serving.