Coat the crock-pot with non-stick cooking spray. Place chicken in crock-pot. Top with onions, sliced bell peppers, mushrooms, and garlic. Add barbecue sauce and sprinkle the packet of Italian dressing seasoning mix over the top. Pour the chicken broth all over.
Cover and cook on low for about 6-7 hours on low or 3-4 hours on high. The time varies depending on your crock-pot. Mine took 6 hours on low. Remove chicken from crock-pot and cut into slices. Add chicken back to vegetables and sauce in crock-pot. Mix to blend.
To assemble each sandwich: On a baking sheet, add the hot dog bun and add 1 cup chicken filling onto the bun. Spoon 3 tablespoons sauce over the chicken. Top with 2 tablespoons cheese. Assemble all the sandwiches you want to serve on the baking sheet. Place in the oven and broil for a couple of minutes to melt the cheese and toast the buns. Keep an eye on it so they don’t burn.
Add each to a plate. Serve with a fork and knife. You’re going to need it. Too messy to eat with your hands but oh so good!
For a low carb option: Add 1 cup chicken mixture to each bowl. Spoon 3 tablespoons sauce over the top. Sprinkle each with 2 tablespoons cheese and serve with a fork and knife. Or, make it a cheesesteak salad.