1. Slowly heat butter just until melted and golden, not browned, stirring all the while. Remove from heat.
2. Add flour, salt, and pepper and stir until smooth.
3. Add milk, a small amount at a time, stirring after each addition. Return to heat.
4. Over medium heat, bring to boiling, stirring constantly. Reduce heat and simmer 3 minutes.
5. Use this white sauce as base for other sauces or for soups.