After trying a lot of expensive 'queso' brands at grocery stores, I finally asked a waitress at our favorite Mexican restaurant. Her answer was, "Land o' Lakes White American." It's perfect!

1/4 to 1/2 lb white american cheese from deli counter (just get them to cut a chunk- not slices)
Several tablespoons of heavy cream or half and half
Salsa or picante sauce (optional)

Cut the cheese into cubes, and put in microwave safe bowl. Add 2 tbls of cream. Microwave at 60% for 30 seconds. Stir. Continue to do this until cheese is melted. Stir vigourously, and add cream until you reach your desired consistency. Microwave once more to heat if additional cream was added. Add salsa to taste and stir.