Grilled Coho Salmon Bundles with Saffron, Tomatoes & Olives

2 medium plum tomatoes, cored and cut into medium dice (about 1 cup)
1/4 cup pitted and coarsely chopped black oil-cured olives (20 to 25 olives)
1/4 cup extra-virgin olive oil
1 Tbs. minced fresh garlic (3 to 4 medium cloves)
1/2 tsp. chopped fresh thyme
1/2 tsp. kosher salt; more as needed
Pinch saffron (15 to 20 threads)
Freshly ground black pepper
Four 6-oz. center-cut, skin-on coho salmon portions

Heat a gas grill with all burners on high.

In a medium bowl, combine the tomatoes, olives, olive oil, garlic, thyme, salt, saffron, and pepper to taste.

Set one piece of salmon, skin-side down, on a 12x18-inch piece of heavy-duty foil; sprinkle lightly with salt and pepper. Spoon a quarter of the tomato mixture over the fish and seal tightly. Repeat to make four packets.

Set the foil packets on the hot grate and cook, with the grill covered, until the fish is opaque throughout, about 8 minutes (open a packet and cut into the fish to check). Let the salmon rest for a few minutes before serving.