Spread half of the sliced mushrooms over the bottom of a 9x13-inch baking dish.
Place the eggs and bread crumbs in two separate shallow dishes (pie plates work great for this).
Dip the chicken breasts in the egg, then into the bread crumbs, patting them to adhere.
In a 12-inch skillet, heat 2 tablespoons of the butter over medium heat until melted. Add half of the breaded chicken to the pan and saute until golden brown on both sides, about 5 minutes. Remove the chicken from the skillet and place on top of the mushrooms in the baking dish. Repeat with the remaining butter and chicken breasts.
Sprinkle the remaining sliced mushrooms over the chicken, then top with the shredded mozzarella cheese. Pour the chicken broth into the bottom of the pan.
Bake until the cheese is melted and browned, and the chicken is cooked through, about 30 minutes.
Notes
I recommend using the thin sliced chicken breasts, or chicken tenders.
This dish is also great with Swiss cheese instead of mozzarella.
You can choose to cover the dish with aluminum foil while baking to retain the juices, however the mozzarella cheese will not brown.