Ingredients:

-1 joint of pig of 800 gr env
-1 onion
-1 tomato
-thym
-salt
-pepper

To put the oil and the butter in a pot .Return it the joint of pig with lively fire on all the faces.
To cut the tomato and the onion in small strips.
When the joint is gilded well, to add the tomato and the onion.
To salt, to pepper and to put the thym;
To reduce the fire and to cook slowly during 1h 30 on the way back the joint from time to time.