1 Peel and dice the potatoes into large cubes, then cook for 10 minutes in salted water.
2 Strain the potatoes and put them back in the saucepan, then mash.
3 Add the egg and slowly add the flour to form an even ball. Season.
4 Form the dough into a long thin cylinder on a floured counter, and cut into 2 cm pieces.
5 Roll each piece on the back of a fork to shape the gnocchi. Let sit for 30 minutes.
6 Boil water in the casserole and drop the gnocchi, waiting until they float.
7 Heat the cream and Parmesan in the frying pan while mixing with a whisk. Add the gnocchi, coating them in sauce.
8 Sprinkle with finely chopped sage.