Sauté breadcrumbs briefly in 3 tablespoons butter over medium-low heat. Set aside.
Preheat broiler. Brush baking pan with a bit of oil. Brush rest of oil on fish and sprinkle with salt and pepper. Place fillet about 4 inches from heat source. Change the position of the pan every 2 minutes or so to brown fish evenly. Baste once or twice with drippings from the bottom of pan, or a bit more olive oil. About 2 minutes before the fish is done, spread on the breadcrumbs. Allow 8 to 10 minutes cooking time per inch of thickness of fish. (If fish cooks too quickly, lower heat to 500°F and finish cooking.) Serve with lemon wedges.