In a medium sized frying pan, melt the butter over medium-high heat. Cook the onion, celery, carrots and mushrooms until soft.
Beat the two eggs and then add into the broth. Stir in the poultry seasoning as well.
In a large mixing bowl, combine the fried vegetables and the bread cubes. Pour the broth mixture over the bread cubes and vegetables, tossing to ensure that the bread cubes are coated well.
Place the stuffing into the 9x13 pan. Cover tightly with tinfoil. Bake in the oven for 25-30 minutes, or until the stuffing is heated to at least 165 ° in the middle. (you have to cook the eggs in it)
Remove and serve.
Notes
The more you dry out you bread cubes, the more liquid you are going to have to add. If you use dried out bread cubes, add another 1/2 cup of broth.
The better your broth tastes, the better your stuffing will taste! If your broth isn't good, your stuffing won't be good!