Preheat the oven to 375°F (190°C).

Add the softened cream cheese, ranch seasoning, buffalo sauce, milk, cheddar cheese, and 1 ½ cups mozzarella to a large mixing bowl. Mix until smooth and evenly combined.

Bring a large pot of salted water to a boil. Cook the lasagna noodles according to the package directions until al dente. Drain well and arrange them flat on a clean surface so they do not stick together.

Spread a thin layer of the cheese mixture across the bottom of a 9×13-inch baking dish. Arrange a layer of cooked lasagna noodles over it.

Spread more cheese mixture over the noodles, then add an even layer of shredded chicken. Continue layering the noodles, creamy buffalo ranch mixture, and chicken until the ingredients are used.

Finish the Buffalo Ranch Chicken Lasagna with a layer of cheese mixture. Sprinkle the remaining ½ cup mozzarella evenly over the top.

Cover the baking dish tightly with aluminum foil. Bake for 45 minutes.

Carefully remove the foil and bake uncovered for another 10 minutes, or until the mozzarella is melted, bubbly, and lightly golden.

Remove from the oven and allow the lasagna to rest for 8–10 minutes before slicing. Finish with ranch dressing, chopped green onions, or blue cheese crumbles if desired.