Cook the pasta in salted water according to the instructions on the packet until soft. Hard boil eggs. Cut the cucumber into small cubes. Drain the mushrooms. Drain the asparagus as well, but collect the asparagus water. Cut the asparagus into pieces approx. 1 - 2 cm long. Drain the peas and carrots, halve the carrots if necessary and cut into slices. Peel the eggs and cut them into cubes.
In a large salad bowl, mix together yogurt, sour cream, oil, vinegar, sugar, mustard, mayonnaise, a little asparagus and cucumber water and season well with salt and pepper. Fold in the remaining ingredients as well as the cold pasta and let it steep. Then add a little mayonnaise, cucumber water and salt to taste.