How to Make It
In a food processor, combine the garlic, greens, parsley leaves and the 3/4 cup of pumpkin seeds; pulse until finely chopped. With the machine on, slowly drizzle in the olive oil. Stir in the 1 cup of cheese. Season with salt and pepper.
In a pot of salted boiling water, cook the spaghetti until al dente. Drain, reserving 1 cup of the pasta water. Return the pasta to the pot. Add the pesto, lemon juice and 1/2 cup of the pasta water. Season with salt and pepper and toss over low heat until coated, about 2 minutes; add more pasta water if a thinner consistency is desired.
Transfer the pasta to bowls and garnish with pumpkin seeds and cheese.