Preheat the oven to 400°F.
On a baking sheet, toss the mushrooms with 1 tablespoon olive oil and a pinch of salt. Roast until browned, about 10-15 minutes.
Bring a large pot of salted water to a boil. Add the pasta and cook according to package instructions. Drain the pasta, return to the pot, and drizzle with olive oil.
In a food processor, blend the arugula, garlic, parmesan, 1/4 cup olive oil, pine nuts, lemon juice, salt and pepper until smooth.
Toss the pasta, mushrooms, roasted red peppers and olives with the pesto sauce until evenly coated.
Divide the pesto pasta between plates and top with parmesan.