Peppery arugula pesto is the perfect accompaniment to grilled Italian sausages. Save any extra pesto to use on other grilled meats or fish. It will last up to one week in the refrigerator.
Make the pesto: Place the arugula and garlic in the bowl of a food processor. Pulse until finely chopped, scraping down sides if necessary. Add cheese, salt, pepper, and olive oil, and puree until smooth and well combined.
Heat grill to medium-high heat. Prick sausages with fork to allow excess fat to drip. Grill until cooked through, about 4 minutes per side. Serve pesto over the grilled sausages.