1.Place A Large Skillet Over Medium Heat; Cook The Ground Beef, Onion, Celery, And Green Bell Pepper In The Hot Skillet Until The Beef Is Completely Browned, 7 To 10 Minutes. Sprinkle The Oats, 3/4 Teaspoon Salt, The Garlic Powder, And 1/8 Teaspoon Black Pepper Into The Beef Mixture. Arrange The Cabbage Wedges Atop The Beef Mixture. 2.Stir The Tomato Sauce, Cider Vinegar, And Brown Sugar Together In A Bowl; Season With Salt And Pepper. Pour Over The Cabbage And Beef Mixture. Place A Cover On The Skillet And Simmer Until The Cabbage Is Tender, 15 To 20 Minutes.