(excuse the blurriness, was using my brothers phone at the time)
500g of minced beef or a even mix of pork and beef1 egg
2dl ketchup
1dl vinegar
1dl water
1 onion, finely chopped
3tsp brown sugar
3tsp Worcestershire sauce
salt and pepper
Mix together the meat with the egg, some salt and pepper and any other flavorings you want.
Shape the meat into relatively thin patties and place them on an oven pan.
Bake them at 175ºC for about 30min.
Melt some butter in a large pot and fry the chopped onion in it until it goes soft and transparent (you don't want them too brown for this, you want them to almost disappear in the sauce later.)
After the onion goes soft add the remaining ingredients and bring to the boil then let simmer for a little while to reduce the sauce.
Taste the sauce often and add more of an ingredient if you think it needs it until you get the right tanginess you want.
Place the burgers in the simmering sauce, if there isn't enough sauce add more water to it and reduce it again until all the burgers are evenly coated.
Serve with a nice potato salad, some nice buns and something cold to drink.
Enjoy!