#1 Heat 1 tablespoon of oil until hot in a wide skillet over medium heat. Add onions stirring occasionally until golden brown. Remove and set aside #2 Season chicken with salt, pepper and garlic. In the same skillet, add remaining oil, add chicken in a single layer and cook for about 4 to 5 minutes on each side or until lightly browned. Remove from pan and allow to cool. Chop and set aside #3 In a wide pan over medium heat, melt butter. Lay one tortilla flat on the pan and sprinkle 1/4 of the cheese on top, chopped chicken, onions, and sprinkle remainder of cheese. Once cheese begins to melt, cover with second tortilla. Cook for 1 to 2 minutes until tortilla is crisp and golden. Flip side and continue to cook until golden and cheese is melted. Repeat with remaining tortillas #4 Cut each quesadilla into fours and serve immediately. Top with sour cream and salsa, if desired!