Preheat the oven to 350 degrees F (175 degrees C).
Place the fish fillets in a shallow baking dish. Sprinkle with garlic, and squeeze lemon juice over them. Dot with pieces of butter.
Bake for 20 to 25 minutes in the preheated oven, until the fish flakes easily with a fork. Spread steak sauce on the cut side of the bottoms of the buns. Top with pieces of fish, then drizzle with Ranch dressing. Place the top buns over the filling, and serve.