I use a pita bread base, then tomato paste sauce over the base and add any combo of the following,
onion, tomato, baby spinach leaves, zucchini, mushroom, capsicum, egg, ham, salami, cheese, and chicken (we buy thigh fillets, marinate in teriyaki or bbq sauce and pan fry for a few mins before adding to the pizza) and then top with cheese! You could add bbq sauce over the whole thing too if you like!