To a small bowl add all of the sauce ingredients. Whisk well and store in the fridge.
To a skillet over medium-high heat, add the ground beef, break it up, and cook it through. Remove any excess grease from the pan. Stir in the ketchup and mustard.
To a clean greased skillet over medium-low heat, place a tortilla down and sprinkle it with cheese, the ground beef mixture, pickles, onion, more cheese, and any other hamburger toppings you enjoy. Place a second tortilla over the top and spray with oil spray. Cook on medium-low for about 4 minutes on each side, or until the tortilla is crispy and the cheese is melty. Repeat for all of your quesadillas.
Serve the quesadillas with the special sauce and enjoy!