Wash the seedless green grapes thoroughly under cool running water and pat them dry. Remove the stems and prick each grape with a fork several times.

In a large bowl, combine the grapes with Prosecco and vodka, then cover and refrigerate for at least 6 hours or overnight.

Drain the grapes in a colander and pat them dry to retain some moisture for sugar adherence.

Roll each grape in granulated sugar on a plate until fully coated.

Skewer 2-3 grapes onto toothpicks, lay on a baking sheet lined with parchment paper, and freeze for 2-3 hours until solid.

Serve directly from the freezer as a refreshing snack or cocktail garnish.