1. Spread tomatoes and cucumber on a rimmed baking sheet and freeze until just frozen, about 45 minutes.
2. In a food processor, mix frozen vegetables, tomato juice, lemon juice, sriracha, Worcestershire sauce and salt. Pulse until mixture is a fine slush, scraping down sides of bowl a few times if necessary. If pieces are too frozen to process, leave mixture to thaw at room temperature for 5 minutes and try again.
3. Add vodka or gin to food processor and pulse once to mix. Divide mixture between 2 glasses. Garnish with olives and celery and serve with straws, if desired.