In A Large Skillet, Cook Beef And Onion Over Medium Heat Until Meat Is No Longer Pink; Drain Well. Transfer To A Greased 3-Qt. Slow Cooker; Stir In The Cheese, Salsa And Garlic Powder. Cover And Cook On Low For 3-4 Hours Or Until Heated Through. Stir; Serve Warm With Tortilla Chips Or Cubed Bread.