Heat oven to 350°F. In small bowl, combine refried beans and taco seasoning. Spread mixture on bottom of 12-inch pizza pan. Layer green onions, SPAM®, chili and cheeses in pan. Bake 20 to 25 minutes or until hot and cheeses are melted. Spread sour cream over top. Sprinkle with olives. Serve with salsa and tortilla chips.