Cook the pasta in salted water according to the package instructions, then rinse with cold water so that it does not stick later.
Mix the yogurt, cream, chopped herbs, onion, lemon juice and season with salt and pepper. Drain the mozzarella and cut into thin slices like the tomatoes.
Now layer pasta, tomatoes and mozzarella alternately in a large bowl and finish each layer with a little sauce. After the last layer, pour the remaining sauce over the salad and let it steep in the refrigerator for about 2 - 3 hours.