Toast the chile peppers in a saucepan over medium-high heat, pressing them flat with a metal spatula and turning occasionally, for 2 to 3 minutes. Add the stock and bring to a boil. Reduce the heat to a simmer and cook until the chiles are tender, 15 to 20 minutes. Puree the chiles and stock in a food processor, then return the mixture to the pan. Add the ketchup, 2 tablespoons vinegar, brown sugar, Worcestershire sauce, maple syrup, tequila and 2 garlic cloves. Grate enough zest from the limes and orange to make 1 tablespoon each; add to the pan along with the juice of 1 lime and the orange. Reduce the heat to a low boil and cook for 20 minutes. Add the chicken and stir to coat with the sauce.
Meanwhile, heat 1 tablespoon EVOO in a skillet over medium-high heat. Add the bacon and cook until browned. Add the chopped onions and the remaining 2 garlic cloves and cook until soft, 3 to 4 minutes. Stir in the beans and cook until heated through. Stir in the steak sauce and pepper.
Combine the juice of the remaining 2 limes and the remaining 1/4 cup vinegar in a large bowl. Grate the remaining onion half into the bowl and whisk in the remaining 1/3 cup EVOO. Add the cabbage and toss to combine. Season with salt and pepper. Drain the slaw before using.
Char the tortillas for 30 seconds on each side. Place some of the chicken mixture on the edge of each tortilla, top with Cheddar, beans and slaw, then tuck in the sides of the tortilla and roll up tightly.
Put the chicken in a very large stockpot or divide between 2 pots if necessary. Add the peppercorns, garlic, bay leaves, carrots, celery, lemons, onions and herb bundle and sprinkle with salt. Add enough water to cover the chicken. Bring to a boil, then reduce the heat to low and cook at a rolling simmer for 1 1/2 hours. Remove the chicken from the liquid and let cool. Strain the stock. (You should have 5 to 6 quarts stock.) Remove the skin and bones from the chicken, and shred the meat using your hands or 2 forks.
The chicken can be refrigerated in the BBQ sauce for a make-ahead meal. Reheat over medium heat, stirring. The beans and the slaw can be refrigerated separately until ready to use.