This is great quick gravy if you find yourself needing some and don't have time for better recipes. It'll do the job! Actually quite decent considering the lack of effort required!
Place all the ingredients in a pan and whisk together
Bring to the boil and keep whisking until there are no lumps
Turn down and simmer and thicken for 5-10 mins, stirring
Add flour or water and whisk to change consistency if necessary