Soak half of the onion in cold water for about 10 minutes. Dice the other half finely.

In a large bowl, combine ground meat, diced onion, soaked onion, parsley, breadcrumbs, egg, paprika, ketchup, duck sauce, salt, and pepper until just combined, about 3-4 minutes.

Divide the mixture into four portions and shape each into a patty, making a small indentation in the center.

Preheat grill to medium-high (about 400°F or 200°C) and brush grates with oil. Brush patties lightly with olive oil.

Grill patties for 6 minutes on one side. Flip, brush with glaze mixture, and cook for an additional 5 minutes until internal temp reaches 160°F (71°C).

Toast burger buns on the grill for about 1-2 minutes. Assemble burgers with toppings of your choice.