I use the left-over sauce to use with pasta for another time, and used low-fat ricotta cheese. I got away with using our small food processor.
2 bunches spinach (to yield 3/4 pound trimmed leaves)
1 1/2 tablespoons unsalted butter
1 large or 2 small cloves garlic, minced
1/2 cup whole-milk ricotta cheese
1/2 cup Parmesan cheese
Salt and pepper
1 pound dried fusilli
Separate spinach leaves from stems. Wash and drain. Weigh out 3/4 pound leaves.
Put the spinach leaves in a 12-inch skillet with just the water clinging to them. Cover and cook over moderate heat until leaves are just wilted, about 3 minutes, tossing once or twice with tongs so leaves wilt evenly.
Transfer wilted leaves to a sieve and place under cold running water until cool. Drain well and squeeze between your hands to remove excess water. The spinach does not need to be thoroughly dry.
Melt butter in a small skillet over low heat. Add garlic and saute 1 minute to release its fragrance. Put spinach, garlic and butter in food processor and process to chop. Add ricotta and process until smooth, stopping machine to scrape down sides of bowl once or twice. Transfer to a bowl. Stir in 1/2 cup Parmesan and season with salt and pepper.
Cook pasta in a large pot of boiling salted water until al dente. Drain, reserving 1 cup water. Transfer to a large warm bowl. Add as much of the sauce as you like and toss to coat, adding reserved water as necessary to thin the sauce. Refrigerate any remaining sauce.
Pasta Harvest, Janet Flecther, 1995