Preheat oven to 450°. Line 2 baking sheets with aluminum foil. Toss Brussels sprouts and onion with 3 tablespoons Country Crock® Spread on 1 prepared pan. Arrange cod on other prepared pan. Combine remaining 3 tablespoons Spread, crumbs and garlic in small bowl; sprinkle evenly over cod.
Bake 15 minutes or until Brussels sprouts are lightly browned and tender and cod flakes with a fork. Sprinkle Brussels sprouts with Parmesan; toss.
Spoon Brussels sprouts on plates and top with cod.