Cook noodles according to package direction, drain.
Meanwhile, in large baking dish, add chicken breasts, ¼ cup buffalo sauce, salt, pepper, and ½ of the packet of ranch seasoning. Toss until chicken is thoroughly coated. Marinate 30 minutes.
In a large skillet over medium heat, heat olive oil, then add chicken. Cook until no longer pink, about 8 minutes per side. Remove from skillet and let cool, then chop into bite-size pieces.
In the same skillet, add butter and cook garlic. Add remaining ¼ cup buffalo sauce and cream cheese and whisk until combined. Slowly whisk in milk and remaining ranch seasoning. Add noodles, mozzarella and chicken to skillet.