In a large skillet, cook bacon over medium heat until partially cooked but not crisp. Add onion and garlic; cook until golden brown, stirring occasionally, 10-15 minutes.
Remove from heat; stir in bread crumbs, tomatoes and parsley. Set aside.
Preheat oven to 400°. Spread oil and butter in an ungreased 15x10x1-in. baking pan. Place fillets in pan. Drizzle with lemon juice and sprinkle with salt. Top with bread crumb mixture.
Bake, uncovered, 10-15 minutes or until fish flakes easily with a fork.