Peel the onions and cut into thin rings. Season the onion rings with paprika and raw cane sugar.
Heat a pan with the oil and roast the onion rings in it until golden brown. Line a bowl with kitchen paper and drain the fried onions in it. Fry the burger patties on both sides in the same pan.
Cut the tomatoes and cucumber into thin slices.
Divide the burger buns and toast them on both sides. Put a tablespoon of hamburger sauce on each side. Put some lettuce on top. Place the burger patties and one slice of each on the lettuce. Finish with cucumber slices, tomato slices and fried onions.