Cut cheese into cubes and place in a crockpot. Pour in the milk and butter. Add the can of undrained, diced green chilies, jalapeños, taco seasoning, and garlic powder. Place the lid on the crockpot and set to LOW for two hours. Stir occasionally, about every 30 to 45 minutes. Serve warm.
*** This could be prepared in the microwave. Place all ingredients in a large microwave safe bowl and melt slowly, stirring every 30 seconds until the cheese is completely melted.