Wash and clean the mussels thoroughly. Discard opened mussels. Peel and finely dice the shallots. Wash thyme and shake dry. Grate parmesan finely
Bring wine, shallots and 2 thyme stems to the boil in a large pot. Add the mussels and simmer covered for about 8 minutes at medium heat until the mussels open. Put the mussels and cooking liquid in a sieve and collect the stock. Discard unopened mussels
Remove leaves from 2 thyme stalks. Melt the fat in a pot. Add flour and sweat for about 2 minutes at low heat while stirring. Deglaze with the mussel stock, add saffron, thyme leaves and cream. Let simmer for 3-4 minutes at low heat while stirring. Season to taste with salt and pepper. Remove the mussels from their shells. Add mussel meat to the sauce and stir in. Keep warm
Roll out the pasta dough and cut in half (28 x 64 cm). Repack the remaining dough well, put it in the fridge and process it in another way as soon as possible. Cut the other half of the dough into 36 squares (7 x 7 cm). Bring a large pot of salted water to the boil and cook the dough in 3 portions for about 4 minutes. Drain. Place 3 lasagne plates on a plate, alternating between mussels and sauce. Layer the remaining pasta plates, mussels and sauce in the same way. Sprinkle with Parmesan cheese and garnish with remaining thyme stems