Spoiler: It's not the egg.Credit: Design elements: Getty Images. EatingWell design.Key PointsChefs agree that great bread is the key to a better breakfast sandwich.Fresh, well-baked bread improves texture, flavor and structure.Piping-hot, well-cooked ingredients elevate homemade breakfast sandwiches.As a native New Jerseyan, my go-to breakfast sandwich is a pork roll, egg and cheese on a kaiser roll. It's what I would order after a late night ou…