Australians love beetroot with their burgers, but this idea is actually from Sweden, where beetroot is added to the meat to give it a sweet tang.
Finely chop the onion. Heat the butter and olive oil in a fry pan and cook the onion slowly until pale and soft, then cool.
Combine the minced beef, egg yolks, capers, sea salt and pepper in a bowl, add the onion and mix together thoroughly. Add the pickled beetroot and juice, and mix well. With wet hands, shape the mixture into 4 large, flat burgers (the traditional method) or make 8 smaller, taller patties.
Heat a ridged cast-iron grill pan, oil it and the burgers lightly, and cook them on a medium heat for about 5 minutes each side. (Alternatively heat a little olive oil in a fry pan and cook the burgers over medium heat until brown on each side.)
Meanwhile, toast the muffins. Serve the burgers in the toasted muffins, with a little salad of green leaves, or with wilted spinach and small boiled potatoes.
© 2002 Jill Dupleix. All rights reserved.