Clean the mussels and check that they’re alive: If they are open, lightly rap them against the tabletop. If they close they are alive, but if they stay open they’re dead and should be tossed out.
Peel the onion and garlic and clean the leek. Slice the vegetables finely and put them in a pot with a little butter.
Sauté them with thyme but not too long or the vegetables lose their color. Add the mussels and stir well.
Add the cider and beer, put a lid on the pot and let the mussels steam for 4-5 minutes, until they open. Those that don’t open must also be tossed out.
Strain off the mussel broth and boil it with cream (about 5 minutes). Put the mussels aside in the pot with the lid on.
Chop the parsley coursely, add the mussel bouillon and season to taste with salt, pepper and if you like a little fresh beer. Pour the bouillon over the mussels and serve them with fresh whole-grained bread.