If you want something truly wonderful try making it with Sodium Citrate. It follows the idea of modernist cooking. The sodium citrate causes the oil not to separate from the fat in cheese so you can melt cheddar, or any cheese, like velvetta. I use 382 grams of milk and warm it until simmering, mix in 16 grams of sodium citrate and then 14.6 oz of cheese. It all melts creamy and smooth and then I pour that over 1 pound of cooked pasta.
You can then always add bacon or jalapenos... but it is quite yummy.