Braise the onions and mince in preheated oil on moderate temperature, until the mince turns to bits and changes color, for about 15 min.
Cut the bacon into small pieces and add it. Stir and cook about another 5 min. Pour the beans into a deep ceramic baking tray.
Mix together the brown sugar, balsamic vinegar, mustard, Worcestershire sauce and remaining spices. Stir well to mix. Pour this sauce over the beans.
Add the mince and bacon and stir again. Put the tray in the oven, bake uncovered about 50-60 min.