This is my absolute favorite way to use leftover carnitas. Use store-bought or homemade carnitas, then fill them with melty Oaxaca cheese and top them with pico de gallo and guacamole.
Warm the shredded carnitas in a skillet over medium heat for 2–3 minutes until hot and slightly crispy at the edges.
Lay one tortilla flat. Sprinkle about ¼ cup of the cheese over half the tortilla, then add a portion of carnitas. Top with 2 more tablespoons of cheese and fold the tortilla over.
Heat a large skillet over medium heat and lightly grease it with butter or olive oil. Cook the quesadilla for 2–4 minutes per side, until the tortilla is golden brown and the cheese is fully melted. Repeat with remaining tortillas.
Cut each quesadilla into wedges and serve warm with pico de gallo and guacamole on the side.