Onion Sausage Quesadillas are a delicious and savory Mexican-inspired dish. These quesadillas are filled with flavorful sautéed onions, spicy sausage, and gooey melted cheese. The combination of the sweet onions and the spicy sausage creates a perfect balance of flavors. These quesadillas are easy to make and can be enjoyed as a quick snack or a satisfying meal. Serve them with salsa, guacamole, or sour cream for a tasty dipping sauce.