Grilled Salmon with Walnut-Arugula Pesto

1/4 cup walnut halves
2 cups loosely packed fresh arugula (2oz)
1 cup loosely packed fresh basil (1/2 oz)
3 tablespoons freshly grated parmesan
1 medium garlic clove
5 tablespoons ex-virgin olive oil
kosher salt
4 6-8oz skinless salmon fillets
freshly ground black pepper

-In a small skillet over medium heat toast the walnuts, stirring occasionally, until fragrant and a shade darker (about 5 minutes)
-Let cool slightly on a plate, about 3 minutes, and then transfer to a food processor
-Add the arugula, basil, parmesan, & garlic to the food processor and process until the mixture is finely chopped-about 1 minute
-With the motor running, slowly add 4 tablespoons of the oil until it’s well combined
-If you’d like, add 1 tablespoon of water to thin the pesto
-Transfer the pesto to a bowl & season to taste with salt
-Start with a clean grill & heat to medium high
-Rub the salmon fillets all over with the remaining 1 tablespoon of oil & then 1/2 teaspoon salt and 1/4 teaspoon pepper
-Put the fillets on the grill, skin side up, & cook until well marked-about 5 minutes
-Flip and continue to cook until opaque in the center, about another 5 minutes
-Serve with the pesto
Serves 4