Roll out dough in a pasta machine, according to the manufacturer’s instructions, to form thin sheets about 1/16-inch thick. As sheets of dough are rolled out, cover with a clean cloth to prevent them from drying out. Cut pasta into 4-inch squares and set aside.
In a large bowl mix together crème fraiche, ricotta cheese, parmesan and grated nutmeg. Season to taste with salt and freshly ground pepper.
Divide the number of pasta squares by half. In one half, place spoonfuls the ricotta filling. On the other reserved squares, brush with egg wash and turn over onto filled squares.
Press firmly around the edges to seal.
Cook ravioli in a large saucepan of boiling water and cook until pasta is al dente, about 6 to 8 minutes.