Cook the pasta in boiling salted water for about 10 minutes. Clean, clean and quarter the mushrooms. Drain noodles, rinse with cold water and drain. Heat 1 tablespoon of olive oil in a frying pan, fry the mushrooms for about 5 minutes, turning them over. Add vinegar and 2 tablespoons of olive oil.
Stir in the noodles and fill into a bowl, let it cool down. In the meantime clean and wash the lamb's lettuce. Wash, clean and slice the tomatoes. Clean and wash spring onions and cut into rings. Wash beef fillet, dab dry and cut into strips. Season with salt and coarse pepper. Put oil in the pan and fry beef fillet for 3-5 minutes. Take out. Mix yoghurt and horseradish. Season with salt, pepper and sugar.
Put oil in the pan and fry beef fillet for 3-5 minutes. Take out. Mix yoghurt and horseradish. Season with salt, pepper and sugar. Stir tomatoes, spring onions and beef tenderloin into the noodles. Fold in lamb's lettuce. Arrange in bowls and sprinkle with horseradish yoghurt