Luke chop onion and fry in the oil and the butter until golden, season with pepper. Add the meat cut into pieces, pour water, enough to cover the meat. Cover with a lid and let it cook on medium stove for 30 minutes. When the meat is cooked is removed and in its place put the olives and crushed with a fork blue cheese. Add cream and stir. Allow another 10 minutes on low heat. The meat is served sprinkled with sauce.