Big Mac Quesadillas

Name: Big Mac Quesadillas
Ingredients: 3/4 c. mayonnaise; 3 tbsp. yellow mustard; 1 tbsp. ketchup; 1 tbsp. pickle relish; 2 tsp. apple cider vinegar; 1/2 tsp. garlic powder; 1/2 tsp. onion powder; 1/4 tsp. sweet paprika; Kosher salt; 1 tbsp. extra-virgin olive oil, divided; 1/2 lb. ground beef; kosher salt; freshly ground black pepper; cooking spray, for pan; 4 medium flour tortillas; 4 slices American cheese; 1 c. shredded cheddar; 1/4 white onion, finely diced; Sliced bread and butter pickles, for serving