Preheat oven to 450°F. Combine chicken and barbecue sauce in small bowl. Let mixture stand 15 minutes. (Can be prepared 2 hours ahead. Cover mixture and refrigerate.)
Place pizza crust on baking sheet. Spread chicken mixture over. Arrange onion, bell peppers, sun-dried tomatoes and pine nuts over. Sprinkle with oregano. Season lightly with salt and pepper. Spread cheese evenly over. Bake pizza until crust is crisp and cheese bubbles, about 17 minutes.
