INSTRUCTIONS
1. In a blender, combine the arugula, mint, olive oil, the ½ cup cheese, the garlic, lemon zest, salt and pepper and blend until smooth. Stir in 1 Tbs. of the lemon juice. Taste and adjust the seasonings with salt and pepper. Refrigerate the pesto until ready to serve.
2. Bring a large pot of salted water to a boil over high heat. Add the pasta and cook until al dente (tender but firm to the bite), 10 to 12 minutes, or according to the package instructions. Reserve ½ cup of the pasta cooking water. Drain the pasta and return it to the empty pot.
3. Toss the pesto with the spaghetti. Thin it out with a small amount of reserved cooking water if needed. Taste, season with salt and pepper, and toss with the remaining 1 Tbs. lemon juice. Divide among warmed serving bowls. Sprinkle cheese over each portion and serve immediately.