On a cutting board, dice the chicken into bite-sized cubes.
Slice the green onions, mushrooms, and zucchini. Cut the zucchini slices into halves or quarters.
Melt the butter in a large pan on medium heat.
Add the chicken, zucchini, mushrooms, salt and pepper to the frying pan. Cook and stir often, until tender, about 5 minutes.
In a bowl, mix together the mozzarella cheese, Parmesan cheese, heavy cream, chicken broth, green onions, beaten egg, basil, salt, and black pepper, until well combined.
Spray an 8×8 baking dish with non-stick spray and pour the chicken and squash mixture in.
Layer the pasta over the chicken mixture.
Pour the cheese mixture over the pasta. Press the pasta until it is all submerged.
Cover with aluminum foil and make sure it is very well sealed around all of the edges.
