Preheat oven to 300°. Line a large rimmed baking sheet with parchment paper.

Place salmon on prepared pan. Brush with 2 tablespoons oil, and sprinkle with ¼ teaspoon each salt and pepper.

Bake until flesh is firm and flaky, about 10 to 20 minutes, or to desired doneness.

In the work bowl of a food processor, place arugula, basil, parsley, pine nuts, thyme, lemon juice, garlic, and remaining ½ teaspoon salt; pulse until finely chopped. With processor running, add remaining ½ cup oil in a slow, steady stream until combined. Serve salmon with pesto and lemon wedges. Garnish with thyme and basil, if desired.