Combine ingredients for the Sweet Mixture in a small bowl. Combine ingredients for the fry sauce in a small bowl. Set aside.
Heat a drizzle of oil in a large skillet over medium-high heat. Add burger patties and cook 3-5 minutes on each side, according to desired doneness.
Spread fry sauce on burger bun and top with patties, some lettuce, tomato and onion slices. Dip fries or onion rings in sauce