Gravy

First the starch.  You can use flour, cornstarch, or arrowroot, but each has differenct thickening capabilities, and each reacts differently to heat.  All purpose flour works fine for most purposes.

The fat can be the fat that remains in the cooking pan.  Pour all of the liquid from the cooking pan into a clear class heat-proof container and allow it to sit for a few minutes until the fat separates from the juices and rises to the top.  Spoon off the fat into a separate bowl, and reserve the rest of the liquid.  If there isn’t enough fat from the cooking pan, add enough butter so that the total amount of fat is sufficient to make the roux, as explained below.

The liquid can be the reserved cooking juices after the fat is separated.  However, you will usually have to add additional liquid.  The additional liquid can be chicken, beef or vegetable broth; or whole milk, depending upon the type of gravy you are making.

Now start by making the roux in the cooking pan.  First scrape up the cooked pieces from the bottom, of the pan (it is best not to use a non-stick pan so that you generate some of these browned pieces).  Now add equal parts of fat and flour to the pan and stir together to form the roux.  How much roux do you need?  The basic formula is 2 tablespoons fat, 2 tablespoons flour, and 1 cup of liquid to equal 1 cup of gravy.

Cook the roux over low heat to eliminate the raw taste of the flour.  If you are going to use a light liquid like chicken broth or milk, cooking the roux for about 5 minutes is sufficient.  If you are making a darker gravy using beef broth, you can cook the roux for 20 minutes or more, until the roux developes a dark brown color.

After the roux has cooked, pour the liquid into the pan while stirring with a whisk to mix.  Make sure the liquid is cool when you add it to the roux.  Bring the mixture to a simmer and as soon as it has thickened it is ready to serve.  You will want to season with salt and pepper.