Preheat the oven to 400°F and drizzle 1 tablespoon of the oil on the bottom of a 9x9-inch casserole dish.
Place the fish fillets in the dish, leaving space between each. Sprinkle on the garlic, salt, and pepper. Scatter the tomatoes over the dish and drizzle with another tablespoon of olive oil.
Bake for 10 to 15 minutes. The flesh should be opaque and flake easily with a fork.