Wash and trim the asparagus and cut into 3 cm lengths. Blanch in boiling, salted water for 6-7 minutes. Drain well. Gently melt the butter, add the lemon peel and sweat briefly. Add the cream and simmer over a low heat for 5 minutes. Season to taste with salt and pepper.
Add the shrimps (thawed if necessary) to the sauce and cook very gently over a low heat for 3-4 minutes. Meanwhile cook the tagliatelle in plenty of boiling, salted water until al dente. Drain, reserving 1 cup of the cooking water.
Mix the tagliatelle with the shrimp cream sauce, asparagus and dill. Stir in 3-4 tbsp of the tagliatelle cooking water. Serve immediately. A fruity white wine goes well with this dish.