In a food processor, process the arugula, freshly grated parmesan and pecorino cheese, half of the pine nuts, and olive oil to the desired consistency. I like it fairly chunky, but some like it smooth. You may need to scrape down the sides of the bowl with a spatula.
Cook the pasta as the package directs. Drain the pasta well and mix it with the pesto to coat. Top the pasta with the remaining pine nuts and sundried tomatoes. Sprinkle it with pepper and salt, if using.