This vibrant — and vegan! — pesto-adjacent sauce is loaded with greens. Arugula gives it a fresh, perky bite, while the avocado makes it super creamy. You also won’t miss the cheese, as nutritional yeast packs a similar punch of umami.
Bring a large pot of salted water to a boil, add the pasta and cook according to the package instructions. Drain, reserving 1 cup of the pasta water. Let the pasta cool for 5 minutes, then toss with 2 tablespoons of oil.
Make the sauce: Put the arugula, avocado, garlic, lemon juice, nutritional yeast, 1 teaspoon salt, the remaining 1/4 cup oil and 1/4 cup of the pasta water in the carafe of a blender and process until smooth, adding a little more pasta water if needed to get the blades going.
Pour the sauce over the pasta and toss to coat. Divide the pasta between bowls and garnish with plenty of pepper, a sprinkle of red pepper flakes and a drizzle of olive oil.