Start with a base ingredient such as vegetables, meat, or seafood
Cook the base ingredient until tender or fully done
Melt butter in a saucepan over medium heat
Add flour and whisk to form a smooth paste
Cook the flour and butter mixture for 1 to 2 minutes
Slowly whisk in milk or cream until smooth
Simmer the sauce until thickened
Season with salt, pepper, and any desired spices
Add the cooked base ingredient to the sauce
Stir until evenly coated and heated through
Serve immediately