Wash and clean the beans and possibly halve them. Cook the beans in salted water for 10-15 minutes. Drain and rinse under cold water. Cut onion into rings. Roast the cashew nuts in a pan without fat, then take them out.
Wash the rosemary and shake dry. Wash the meat, dab dry and season with salt and pepper. Tie the rosemary twig with kitchen string around the meat. Coat a coated pan with oil.
Fry the meat for 8-12 minutes while turning. Remove meat and keep warm. Add blueberries and 2 tablespoons of water to the roasting set and simmer for about 1 minute. Season vinegar with salt, pepper and a little sugar.
Fold down 1 tablespoon of oil. Mix beans, red onions, cashews and vinaigrette and season with salt, pepper and a little sugar. Arrange meat with blueberry sauce and bean salad.