Preheat the oven to 350 degrees F (175 degrees C).
In a medium bowl, stir together the mustard and olives. Dip each chicken liver in the mustard mixture, then wrap with a slice of bacon. Secure bacon with toothpicks. Arrange the livers in a single layer in a baking dish.
Bake for about 20 minutes in the preheated oven, or until livers are firm and bacon is browned.