4. Lightly flour 2 jelly-roll pans. (If you plan to freeze the gnocchi, line the pans with parchment and flour the parchment.) Divide the dough into 8 pieces. On the floured work surface, roll one piece of dough into a rope about half an inch in diameter. Cut the rope into three-quarter-inch-long pieces. Hold a fork vertically in one hand, with the back of the fork facing you. With an index finger, press one of the gnocchi horizontally against the front of the fork and let it fall onto a floured pan. Each of the gnocchi should have ridges on one side (to trap the sauce) and an indentation on the other. Repeat with remaining dough, keeping gnocchi in one layer on the pans.

5. Either freeze the gnocchi on the pans and then transfer them to plastic bags, or cook them the same day. (Gnocchi keep at room temperature for 4 to 5 hours; do not refrigerate.)

6. To cook gnocchi, fill a very large pot with water and bring to a boil. Salt generously (about 2 tablespoons of salt for 4 quarts of water) and add about a quarter of the ­gnocchi. (Do not thaw frozen gnocchi.) Do not stir the gnocchi. In a short time, they will bob gently to the surface. About 10 seconds later, scoop them out with a strainer, drain, and transfer to a serving bowl. Repeat with remaining gnocchi.

Tomato Sauce
4 cups canned peeled tomatoes with their juices,

coarsely chopped

1 medium yellow onion, peeled and halved

4 tablespoons extra-virgin olive oil

Salt