Cheese Sauce
from http://www.seriouseats.com/, J. Kenji López-Alt

This is a cheese sauce for burgers, fries, and chips. Cheese sauce is often just made by melting a block of Velveeta cheese in a double boiler. If you want to make a cheese sauce with something like Cheddar, you run into the problem of the cheese separating, getting gloppy and forming pools of grease. According to the Food Lab at Serious Eats you need to find a way to keep the fat globules from separating out and pooling. J. Kenji López-Alt analyzed the ingredients of Velveeta to find the answer.

After experimenting with different ingredients, he found adding evaporated milk and cornstarch kept the sauce smooth and silky.

You could also add salsa to this dip and call it "con queso" dip, as many do after adding salsa to melted Velveeta.

8 ounces extra sharp cheddar cheese (or a mix of cheddar and pepper Jack), grated on large holes of a box grater
1 tablespoon corn starch
1 (12-ounce) can evaporated milk
2 teaspoons Franks Red Hot or other hot sauce

Add cheese and cornstarch to large bowl. Toss to combine.

Transfer to medium saucepan. Add 1 cup evaporated milk and hot sauce. Cook over low heat, stirring constantly with whisk until melted, bubbly, and thickened (about 5 minutes). Mixture will look thin and grainy at first but will thicken and come together after heating. Thin to desired consistency with additional evaporated milk. Serve immediately with fries, tortilla chips, burgers, or hot dogs.

Makes about 1 1/2 cups