Instructions:

1. Bring a pot of water to a boil. Once boiling, add salt and cook the pasta according to the package instructions.
   
2. Meanwhile, wash and dry the arugula. Finely crush the walnuts.
   
3. In a blender or food processor, combine the sun-dried tomatoes, walnuts, arugula, grated Parmesan, and olive oil. Blend until combined and smooth. If the pesto is too thick, add a little pasta cooking water to loosen it.
   
4. When the pasta is cooked, drain it and mix it with the pesto until well coated. Serve immediately.