1Heat oven to 425°. Grease 12-inch pizza pan. Stir together tomato sauce, oregano, basil, salt, garlic powder and pepper; set aside.
2Stir Bisquick and cold water until soft dough forms. Press dough in pizza pan, using fingers dipped in Bisquick; pinch edge to form 1/2-inch rim. Sprinkle 1/2 cup of the cheese over dough. Spread tomato sauce over top. Top with chicken and olives. Sprinkle with remaining 1 cup cheese.
3Bake 20 to 25 minutes or until crust is golden brown and cheese is bubbly. Garnish with avocado slices.