Wash and dry the spinach. Place it into a food processor, and pulse until it is well chopped. Add the flour and salt and pulse. Lightly beat the eggs in a small bowl, and then add a little at a time to the flour mixture, pulsing briefly between additions. Once the dough has come together into pellet sized pieces, remove and knead by hand until smooth. To Roll Pasta With A Pasta Machine: Break off a fist sized piece of the dough and flatten into a disc. Flour well, then pass it through the widest openings of your pasta machine. Remove, fold into thirds and repeat. Do this 4 or 5 times, dusting with flour between each time. Now start to decrease the rollers by turning down one notch each time. Put the dough through each setting twice until you have reached your desired thickness. For stuffed pastas, you will generally roll it to the thinnest or second thinnest setting.