The first step in this Portillo's cheese sauce recipe is to properly prepare the ingredients. You will need to separate the cheeses into sections. Although this particular Portillo's cheese sauce recipe only calls for cheddar cheese, you can add different types of cheese to your pot.
When doing this Portillo's cheese sauce recipe, it is essential to store the cheese and perishable ingredients in the refrigerator. The cold temperature preserves the cheese and milk needed for this step. I find it easier to combine all cheese and dry ingredients into a zip lock bag, but this is not necessary.
During the second step in Portillo's cheese sauce recipe, set your pan and butter it. The pan should sit on a burner on a medium high. This step is fast though, you will need to watch closely so that the melted cheese does not start to burn and stick to the bottom of the pan.
Add the cheese, cornstarch, and any additional seasonings. While Portillo's cheese sauce recipe does not typically call for jalapenos or added peppers, you should add these additional toppings in the second step. Don't forget to stir. Although you can combine all the ingredients together to simmer, this can make it hard for the cheese to melt.
Cornstarch when overheated burns. You need to mix the cheese and the cornstarch in this Portillo's cheese sauce recipe as smoothly as you can. Take a whisk if the spoon does not work with bubbles of cornstarch.
Now, on to the last step! In the last step during your Portillo's cheese sauce recipe, the process gets simpler! Add the remaining ingredients, which is typically butter, milk, and some kind of cream. The remaining ingredients are a soft liquid that does not need to be melted, but adds flavor and depth.
Bring down the heat to a low and simmer for a minimum of five minutes. As the delicious cheese sauce simmers, it is important to continue stirring slowly. There will be a yellow film that remains on top of the cheese sauce, this is normal!