In a small bowl, beat the egg. Set aside.
In a medium mixing bowl, toss the bread cubes in the melted butter.
Add the egg, zucchini, onion, and garlic salt to the bowl. Mix well.
Transfer the mixture to a 5 qt or larger crock-pot.
Cover and Cook on LOW for 4-6 hours or until the zucchini is fork tender.
Serve and enjoy!