Quick and easy mushroom sauce

This is a sauce I use on beef or chicken burgers or simply as a side for a nice juice steak and chips. I make alot as you can always keep it in the fridge for upto a week and use it as you like.

1 punnet button mushroom or oyster mushrooms

1 small onion

1 tbls butter

2 tbls plain flour

500mls milk

In a medium pot melt butter and lightly saute onions and mushrooms till nice and soft. Add flour and cook till the flour becomes pale and fluffy, slowly add milk to mixture and cook on a medium heat for 5 mins until nice and thick.