1. Preheat broiler. Place pizza crusts, split side up, on baking sheet. Broil 4-5 inches from heat until golden, 30 - 60 seconds on each side.
2. Combine beans, caponata, cherry peppers, vinegar in bowl.
3. Tope each crust with a generous 1/4 c of bean mixture, spreading almost to edge. Sprinkle each with 1/4 cup cheese. Broil until cheese melts, about 1 minute. Serve immediately.