I always wanted to know how to make gravy, my favorite is cream based for 
biscuit, chicken fried steak, etc.  Betty was sick for a couple of weeks this 
winter and I did the cooking so I got to learn.  This is just enough for two, 
you can easily double or triple the recipe.

Put the butter in a pan over medium heat, until it melts. 
If you use heavy cream instead of milk you can just use 2 Tbsp of butter, other
wise add a little for the butter fat, but I don't recommend it.
Add the flour, a little at a time, stirring.
Pour in the heavy cream slowly, and keep stirring until smooth and starts to
thicken.
Salt and pepper to taste.
Pour it in a boat (I use a 2 cup measuring cup) and eat.