Combine lime juice, oil and garlic in small bowl or plastic zippered bag. Add chicken; toss to coat. Marinate 15 minutes; drain.
Cook chicken in large preheated skillet over medium-high heat 5 minutes or until no longer pink; drain if necessary.
Place crust on baking sheet or pizza pan. Spread salsa over crust; top with chicken, cheese and pepper. Bake in preheated 400°F oven 15 minutes or until cheese is melted. Sprinkle with onion or cilantro. Serve with sour cream.