Clean the mussels; remove the beards and scrub well. Discard any that are damaged or broken.
In a large pan fry the garlic in the olive oil, add the wine and reduce by four-fifths. Add the mussels and the peppercorns. Remove the pan from the heat as soon as the mussels are open.
Serve the mussels with parsley sprinkled on top. A mixture of mussels and clams can be used for this dish. A concassé (small dice of fruit or vegetables) of lemon is also good scattered on top of the mussels.