1. Place cabbage in a large microwave-safe bowl; cover with water (about 8 cups). Cover bowl loosely with plastic wrap. Microwave at HIGH 8 1/2 minutes or until cabbage is tender; drain.
2. Preheat oven to 375°.
3. Lightly spoon flour into a dry measuring cup; level with a knife. Combine flour and milks in a small saucepan. Stir with a whisk. Bring to a simmer over medium heat, and cook 2 minutes, stirring constantly with whisk. Remove from heat. Add 1 minced garlic clove, salt, pepper, and cheese to pan, and stir until cheese melts. Pour milk mixture over cabbage, tossing gently to coat. Pour cabbage mixture into an 11 x 7-inch baking dish coated with cooking spray.
4. Place butter and remaining minced garlic clove in a microwave-safe bowl. Microwave on HIGH 25 seconds or until butter melts; stir in crackers. Sprinkle crumb mixture evenly over cabbage mixture.
5. Bake at 375° for 45 minutes or until edges are golden and top is set. Let stand 8 minutes before serving.