1. Add salt to the meat and put it on a oven grid. Heat the oven to 200ºC. Put the meat in the oven and after 10 minutes turn it over and cook for another 10 minutes.
2. Remove the meat from the oven, wrap it in foil and set aside.
3. Mix the juices from the meat with half litre of water to make the sauce. Drain it and pour into a saucepan. Add the rest of ingredients except corn flour.
4. Dissolve the corn flour in a small amount of cold water and add it to the mixture. Stir until slightly thickens. Cut the beef into slices and serve.
5. For the tartar sauce, make a mayonnaise with Borges 2 oil (to underline the taste) and one egg: Boil the other egg for 15 minutes and chop it together with the capers, onion and pickles. Mix all the ingredients.