01 - Set oven to 350°F (180°C) to allow even heating before assembly.
02 - In a large mixing bowl, thoroughly blend shredded chicken breast, softened cream cheese, shredded cheddar cheese, ranch seasoning mix, and whole milk until uniformly combined.
03 - Fold in half of the crumbled bacon to evenly disperse throughout the mixture.
04 - Transfer mixture into a baking dish and bake uncovered for 20 to 25 minutes until filling is heated through and bubbling at the edges.
05 - Gently stir the filling, then generously mound the hot mixture onto the bottom half of each sandwich bun.
06 - Top with reserved bacon and add pickles, lettuce, or tomato if desired. Cover with the top bun and serve immediately while warm.