Watermelon Raspberry Slushies

diced watermelon, deseeded (freeze before blending for 1 hour)

 cups raspberries (freeze before blending for 1 hour)

shots raspberry pomegranate vodka (or your favorite flavored or unflavored vodka), optional

shots raspberry or watermelon schnapps, optional

juice of 1 lime, or to taste

sweetener, optional and to taste (I recommend a liquid sweetener like agave, simple syrup, or a zero-calorie sweetener; granulated sugar may not dissolve entirely)