This is total Tex-Mex comfort food! It's not a King Ranch casserole as there is no cream soup in the recipe. The name has a great story... my family went to visit my grandparents in Waco Texas over 20 years ago and my grandmother made this for dinner. When my mom asked her what it was called she just said, "I don't know.... chicken sling it", meaning she just made it up. I added the chipotle chiles - I like the smoky-spicy kick.
1place chicken and bouillon cubes in a dutch oven and cover with water. Simmer until chicken is done between an hour and an hour and a half. Remove chicken to a cookie sheet with raised edges and let cool about 30 minutes. Reserve the broth to dip the tortillas in.
2While chicken is cooling in a medium pan cook onions and peppers in vegetable oil until tender about 10 minutes.
3Once chicken has cooled, remove chicken from bone, discarding fat as well and place in a large mixing bowl. Cut any large pieces down to bite sized. Add onions and peppers, drained mushrooms, and diced green chiles. At this point i add a little salt and pepper to taste. Add a ladle of the broth to moisten the chicken mixture.
4Open the enchilada sauce and add the chipotle chiles and stir to combine.
5Now you are ready to assemble this bad boy!
Pour have of the enchilada sauce in your casserole dish. Dip a tortilla in the broth and place in the dish over the sauce. Spoon a forth of the chicken mixture over the tortilla. Repeat with the tortilla and then the chicken mixture. Add another dipped tortilla. At this point add half of the shredded cheese then repeat the process with the dipped tortilla and chicken ending with a dipped tortilla on top. Pour remaining enchilada sauce over the top and then the shredded cheese. Bake covered 350 degrees for 30 to 40 minutes.