Cut liver into strips. Wash apples, core and optionally peel, cut into strips. Fry liver for 1-2 minutes in the melted butter, remove from the pan. Pass sliced red onion, add the apples, spices and fry. Return the liver to the pan, pour in broth and cream and simmer 2-3 minutes. Add sauce thickener and season to taste and serve, sprinkled with thyme leaves.