To a pot over medium heat, add heavy cream, evaporated milk, cream cheese, mustard powder, and cornstarch. Whisk together as it heats up until completely smooth.
Once it comes to a boil, add the grated cheddar one cup at a time. Whisk after adding every cup until completely incorporated. Add the hot sauce after adding all the cheese and salt to taste. Whisk again to make sure it's smooth and no chunks.
Enjoy warm with tortilla chips or anything you like!