DirectionsIf using frozen mussel meat, thaw it properly according to the package instructions and drain well in a colander. Add the chopped tomatoes, reduce the heat and simmer for about 10 minutes, until the sauce has thickened. This is important, as the mussels will release additional liquid during cooking. Add the mussels, oregano (or thyme) and crumbled feta. Taste first, as both the mussels and feta are naturally salty.