Remove the woody end of the asparagus, cut into bite-sized pieces and cook in salted water for about 5 - 10 minutes. Then quench in ice water and allow to drain.
Cook the tagliatelle according to the instructions on the packet.
Dice the onion and sauté in the butter in a large pan. Rinse the prawns under lukewarm water, dab and add to the onions. Cook both for about 5 minutes, stirring occasionally. Deglaze with the white wine and add the broth and the cremefine. Now add the asparagus and let the sauce simmer for a few minutes. Season to taste with salt, pepper and dill and, if necessary, thicken with a little liquefied cornstarch.
Drain the pasta well and add to the asparagus and shrimp sauce. Mix well.