This was a recipe my mother used to make when she wanted something other than butter for our potatoes with a meal. I remember as a teen coming home from high school dances and making this to have over toast all the time.
Place 3 Tbs.s butter in a deep pan over medium heat.
Stir in: 1 large chopped onion and cook stirring until transparent.
Sprinkle 2 Tbs. flour over the onion and stir over low heat
until mixed well.
Slowly add 2 cups milk while stirring constantly until mixture
comes to a boil.A drop more milk can be added if it seems too thick.
Add salt and pepper.