Bring a large pot of salted water to a boil.
Meanwhile, make the pesto. Add the arugula and basil to a food processor and pulse until finely chopped. Add the walnuts, garlic, lemon juice, salt, pepper, and goat cheese and process until smooth, stopping to scrape down the sides of the bowl a few times if necessary. With the motor running, slowly drizzle in the olive oil, and process until well incorporated. Taste the pesto and season with a little extra salt and pepper if it needs it. Set aside.
Cook the pasta al dente according to the package directions. Reserve ¾ cup of pasta water, then strain the pasta and briefly set aside. (If you’re using a gluten-free pasta, be sure to rinse the pasta with cold water immediately after straining.)
If you’re embracing the garlicky breadcrumbs, now is the time to make them. Heat the olive oil in a small skillet over medium heat. When the oil is hot and shimmering, add the garlic to the pan and cook until golden brown, about 1-2 minutes. (Be very careful NOT to burn the garlic—if it starts to brown too quickly, turn down the heat!) Add the panko to the pan and cook, stirring regularly, until it darkens a shade in color. Transfer to a small bowl and briefly set aside.
Heat a teaspoon of olive oil over medium heat in the same pot you used to cook the pasta. When the oil is hot and shimmering, add the sausage and cook for 6-8 minutes or until nicely browned. Add ¼ cup of the reserved pasta water to the sausage, using a spatula to loosen any delicious browned bits from the bottom of the pot. Add the sun-dried tomatoes, pasta, and pesto to the pot, and another ¼ cup of the pasta water to the pot. Fold everything together until well combined. (If the pesto is too thick, add the remaining ¼ cup pasta water to loosen.) Cook for 1-2 minutes or until warmed through.
Serve the pasta warm topped with a garlicky breadcrumbs and a little extra fresh basil if you like. An extra sprinkling of goat cheese is always an option too…