5 T. butter
1/2 C. chopped onion
4 C. milk
4 T. flour
1 1/2 t. sugar
1 1/2 t. salt
1/2 t. baking soda (prevents milk from curdling)
3 C. chopped tomatoes (fresh or canned)
Melt the butter in a soup pot. Add the onion and cook over medium heat, stirring until the onion is soft but not browned. Sprinkle flour over the butter mixture and stir cook 1-2 minutes. Slowly add the milk, sugar, and salt. Continue to stir and cook until thickened.
Stir the baking soda into the tomatoes. Add the tomatoes to the milk, and heat to a simmer. Remove from the heat and taste for seasoning. (If desired you may put through a strainer or food mill.) Reheat before serving.