Line a baking sheet with aluminum foil, and place salmon fillets skin side down. Drizzle with salt, and pepper. Spread pesto over the top of fillets with a spoon or small spatula (try to cover them as evenly as possible). Sprinkle thyme over the pesto.
Roast the salmon 4-6 minutes per ½ inch thickness. The fish should flake easily with a fork when it's finished.
If the salmon has skin, remove it now if desired. It should peel off easily. Serve with lemon wedges and fresh basil (optional).