INGREDIENTS For the Pasta 8 ounces penne pasta 4 tablespoons Butter 16 ounces fresh sliced mushrooms ¼ cup grated or shaved Parmesan cheese salt, pepper, and fresh parsley for topping For the Walnut Pesto 1 cup walnuts 1½ cups packed greens (spinach, basil, parsley, anything you like - but keep some basil for a more traditional pesto flavor) ½ to ¾ cup shredded Parmesan cheese ¼ cup olive oil 1 clove garlic juice of 1 lemon salt and pepper to taste INSTRUCTIONS Cook the penne pasta according to package directions. Drain and set aside. Toast the walnuts in a small sauté pan over low heat with no butter or oil - stir and shake the pan until the walnuts are fragrant and toasty (about 5 minutes). In a food processor, combine all the ingredients for the walnut pesto and pulse until mostly smooth. Heat the butter over medium heat in a wide skillet. Add the mushrooms and saute for 8-10 minutes, until the mushrooms are a deep golden brown. Add the penne pasta to the pan and stir to combine, adding Parmesan, salt, pepper, and fresh parsley or other herbs to taste. Divide the pasta between 4-6 bowls and top with a generous spoonful of the walnut pesto OR stir the walnut pesto directly into the pasta.