Melt butter and cream cheese in a sauce pan over medium heat. The cream cheese might look a bit strange it is going to be clumpy and curdled looking but that is how you want it! Once melted stir it until you have it as smooth as you can get it.
Pour in the whipping cream and turn the heat to medium-high.
Whisk together until butter and cream have combined and until the sauce bubbles slightly.
Add Parmesan cheese and garlic powder and stir to combine well. You want it nice and creamy.