Cut American cheese into small cubes and set aside.
Heat ¼ cup of the half and half or milk over medium low heat in saucepan, stirring continuously.
Once it starts to just begin to boil, reduce heat to low and stir in cheese, a little at a time.
Stir constantly until melted, then add some more cheese (each time, just a little at a time) until it all blends together.
Keep an eye on the pan to avoid scorching.
If it gets too thick, add more half and half or milk until you reach the creamy consistency you want it to have. If it seems too thin, just stir in more cheese. This recipe is very forgiving, just keep an eye on the heat.
When the cheese is done, turn off stove and remove from heat. Transfer to serving dish/bowl. Serve with warm corn tortilla chips. Enjoy!!