Heat the broiler. Drizzle the fish with 2 Tbs. olive oil and sprinkle it with salt and pepper. In a separate bowl, toss the cherry tomatoes with remaining olive oil, salt, pepper, and fresh herbs and place on rimmed baking sheet or gratin dish. Set aside.
Broil the fish for about 5 to 8 minutes, depending on thickness, or until firm. When done, the fish will still be firm and juicy but opaque, and a thin-bladed knife will pass through it fairly easily. Cover and keep warm.
Broil the tomatoes until their skins blister and crack, about 3 minutes; check often, shaking the pan frequently to keep them from burning.