Wash, clean and chop the tomatoes. Wash the meat, dab dry and season with salt and pepper. Wash asparagus, cut off woody ends. Cook the asparagus in boiling salted water for about 10 minutes
Heat the oil in a pan and fry the meat for about 6 minutes while turning. Remove meat and keep warm. Briefly toss the tomato cubes in the frying oil. Season with salt
In the meantime, bring vinegar to the boil in a small casserole and add butter cubes bit by bit, stirring until frothy with a blender. Arrange asparagus, sauce, meat and tomato cubes on a plate. Sprinkle with parmesan