Prepare the Burger Filling

Heat the olive oil in a large skillet or cast-iron pan over medium-high heat. Add the diced onion and cook for 3-4 minutes until softened and translucent. Add the ground beef, breaking it up with a wooden spoon. Cook for 5-7 minutes until the beef is fully browned and no pink remains.

Practical Tip: Drain excess grease from the pan if necessary, but leaving a tablespoon or two will enhance flavor and prevent dryness.

Reduce heat to medium. Stir in the minced garlic, Worcestershire sauce, mustard, paprika, salt, and pepper. Cook for 1 minute until fragrant. Add the ketchup and pickle relish (if using). Stir to combine thoroughly and cook for another 2 minutes. Taste and adjust seasoning. Transfer the mixture to a bowl and wipe the skillet clean for cooking the quesadillas.

Assemble the Quesadillas

Lay one tortilla flat on a clean work surface. Sprinkle 1/2 cup of cheese evenly over one half of the tortilla. This first layer of cheese acts as a “glue” for the filling.

Spoon half of the burger mixture evenly over the cheese. Top the beef with another 1/4 cup of cheese, followed by a handful of shredded lettuce, diced tomato, and sliced onion or pickles. Example: For a less soggy quesadilla, keep wetter ingredients like tomatoes in the center, away from the tortilla’s edges.

Sprinkle another 1/4 cup of cheese on top. Fold the bare half of the tortilla over the filled side, pressing down gently. Repeat with the remaining tortilla and ingredients.

Cook to Golden Perfection

Place the cleaned skillet over medium heat. No extra oil is needed if using a non-stick pan; for cast iron, a light brush of oil or butter will promote browning.

Carefully transfer one assembled quesadilla to the hot skillet. Cook for 2-3 minutes per side, pressing down lightly with a spatula, until the tortilla is golden brown and crispy and the cheese inside is fully melted.

Cooking Tip: To ensure even cooking and melting, cover the skillet with a lid for the last minute of cooking each side. This traps steam and guarantees a gooey center.

Remove the quesadilla to a cutting board and let it rest for 1-2 minutes before slicing. This allows the filling to set slightly, preventing a messy spill when cut. Repeat with the second quesadilla.

Serve and Enjoy

Use a sharp knife or pizza cutter to slice each quesadilla into 3 or 4 wedges. Serve immediately with small bowls of ketchup, mustard, and mayonnaise or Thousand Island dressing for dipping.