Place the bread cubes in a large bowl and set aside. Preheat oven to 350 degrees F. and grease a 9x13" or similar size casserole dish and set aside.
Melt the butter in a large skillet over medium-high heat. Add in the onion, garlic, mushrooms and celery, sauté until tender, about 5 minutes.
Add vegetable mixer to the bowl of bread cubes. Pour in the chicken broth, eggs, poultry seasoning, thyme, salt and pepper. Stir to coat the bread cubes evenly, then pour mixture into the prepared baking dish.
Bake for 30 to 35 minutes, or until the top is golden brown and the center reads 165 degrees F. Enjoy!
How To Make Your Own Bread Cubes:
Cut out 12 cups of bread (sandwich, french bread, sourdough, etc) and place in an even layer on large rimmed baking sheets.
Place in a 300 degree oven for 10 minutes, until the bread is dried out.