Bechamel sauce is basic white sauce made with butter,flour and milk as main ingredients.
Heat butter - when it is melting add the flour.
Cook the flour for 3-5 mins then immediately add milk.
Cook in medium flame, it will bubble.Keep stirring with a whisk.Whisk vigorously until smooth so that there are no lumps forming. It will start to thicken,I switched to spatula now.
It will form a smooth creamy paste like consistency,It should coat the laddle, and when you draw a line it should stand still as shown in the picture.This is the right consistency.
Add salt and pepper.If you want you can add nutmeg powder too.Mix well and switch off.Now the basic white sauce is read.You can add cheese if you prefer at this stage. It depends on the recipe you want to use this recipe.