In a skillet over medium heat, brown the ground beef for about 6-8 minutes, breaking it apart as it cooks. Drain excess fat.

Add the diced onion to the skillet. Cook until the onions are translucent, about 3 minutes.

On one flour tortilla, sprinkle half of the shredded cheddar cheese. Layer the cooked beef mixture evenly, followed by the pickles. Add another layer of cheese, then fold the tortilla like a taco.

In the same skillet, cook the folded quesadilla over medium heat for about 3-4 minutes until golden brown and crispy. Flip carefully and cook the other side.

Let the quesadilla sit for a minute, then slice into wedges. Serve with ketchup and mustard for dipping.