Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking dish or casserole dish and set it aside.

In a large mixing bowl, combine the shredded rotisserie chicken, condensed cream of chicken soup, frozen vegetables, and ranch dressing mix. Mix them together until well combined.

In a separate bowl, beat the softened cream cheese until it's smooth and creamy.

Add the cream cheese to the chicken and vegetable mixture. Stir well to incorporate the cream cheese evenly into the mixture.

Spread the creamy chicken and vegetable mixture evenly in the prepared baking dish.

Sprinkle the shredded Monterey cheese over the top of the casserole.

In a small bowl, combine the crushed Ritz crackers, Italian herbs seasoning blend, and garlic salt. Mix them together.

Sprinkle the cracker mixture evenly over the cheese layer in the casserole dish.

Bake in the preheated oven for about 25-30 minutes or until the casserole is hot and bubbly, and the top is golden brown.

Remove from the oven and let it cool slightly before serving.