White roux: In a small heavy saucepan melt fat over medium heat. Add flour, whisking to incorporate fully, and stir for 2-5 minutes until the mixture is bubbly and foamy.

For Blonde Roux: Continue cooking and stirring for 5-10 minutes, until the mixture turns a light caramel or peanut butter color.

For Brown Roux: In order to avoid burning your roux, turn down the heat to medium-low and keep stirring. You'll need to keep cooking for an additional 5-15 minutes. For a total of (15-25 minutes). The roux will take on a nutty aroma when it's done and turn a milk chocolate brown.

For Dark Roux: Continue cooking and stirring for an additional 20+ minutes, or until the roux is a dark chocolate color. Be careful not to burn it! If it smells burned at all, you need to start over.