Ingredients
2 large ruby grapefruits, juiced, or 1 1/2 cups pink grapefruit juice
1 tsp. grapefruit zest (zest before juicing grapefruit)
1/2 cup water
1 cup granulated sugar
1 tbs. vodka
1 tsp. grenadine (optional)
Preparation
Combine the sugar and water in a small saucepan; bring to a boil and stir to dissolve sugar. Cool completely.
Combine the grapefruit juice, zest and sugar/water mixture with the vodka and optional grenadine (for color) in a metal bowl. Chill in the refrigerator or by placing the metal bowl over a larger bowl filled with ice water until 40 degrees.
Pour chilled mixture into container of an ice cream machine and churn until frozen.
Scoop frozen sorbet into a container. Seal and transfer container to freezer for several hours to allow sorbet to firm up. (Sorbet can be kept frozen for up to 3 days.)