Set salmon on a plate and season with salt and pepper. Let salmon stand at room temperature about 20 minutes. Meanwhile, prepare a grill for two-zone medium heat grilling (350° to 450°F). For gas, preheat the grill with all the burners on, then turn off the center burner or one of the side burners. The area with no heat underneath it is indirect heat. For charcoal, ignite half a chimney of charcoal. Spread lit coals over only half of the fire grate; the area with no coals is for indirect heat. Set the cooking grate in place and let heat 10 minutes.

As the grill heats, make the relish. Toast pine nuts in a small skillet over medium heat, stirring often, until lightly browned and aromatic, 5 minutes. (Watch carefully, as pine nuts burn easily). Once toasted, place in a medium bowl.

Add the tomatoes, parsley, olives, capers, balsamic vinegar, 1 tablespoon olive oil, and garlic to the bowl with the pine nuts. Stir to combine, and then set aside.

Just before cooking, oil the cooking grate to keep the fish from sticking. Use tongs to hold a small wad of paper towel slicked with a little olive oil and rub the towel over the grates on the cool side of the grill.

With a metal spatula, lay the salmon skin side down on the cooler, indirect heat side of the grill, opposite the flames. Then cover the grill. This makes the grill like an oven. Grill until the salmon is opaque and flakes easily when you press it with your finger, 5-10 minutes, depending on the heat of the grill and the thickness of the fillets. A thermometer inserted into the thickest part of the fillet should read 120? for medium-rare (pearly); or cook it longer if you prefer. You can also slide a paring knife or metal cake tester into the fillet, then withdraw it and touch the metal: if it’s cool, keep grilling. If it’s quite warm, you’re good to go.

Serve the salmon with the relish on the side or spooned over the top.