Drizzle the cod fillets with lemon juice and season with salt and white pepper.
Cook the pasta al dente according to the instructions on the packet.
Melt the butter in a saucepan, add flour and make a light seared burn over low heat. Pour in water while stirring constantly. Add the cream and season with lemon juice, salt and pepper.
Add the cod fillets to the sauce and poach in it for 6 minutes, turn after 3 minutes. Wash the dill, shake dry and cut very finely. Add the dill to the sauce, let the sauce boil briefly, season to taste again and arrange the fish with the sauce and pasta on two plates and serve.