After rolling out the dough with an old-fashioned Atlas machine, Domenica Marchetti tests the pasta sheets by holding her hand up behind one. If she can see a shadow, the sheets are the right thickness to stuff. "The dough should be thin, but still have substance and texture," she says.
Tip: "Always err on the side of making ravioli dough a little bit sticky," Marchetti says. "You can sprinkle on more flour as you roll it out."