Red Sangria Slushie

In a saucepan, cook berries, 1/4 cup water, sugar, and vinegar over medium-high heat until fruit has softened, about 5 minutes, smashing berries with a potato masher. Strain through a fine-mesh sieve, pressing as much liquid out as possible. Discard seeds. Cool liquid.

Combine juice and wine in a quart-size zip-top bag. Seal bag and freeze overnight. To serve, massage the bag to break up mixture. Tip slushie into a glass. Add garnish and serve immediately.