In a bowl, whisk tomato sauce, tomato paste, vinegar, maple syrup, Worcestershire, spices, mustard, and broth until smooth.
Pat dry and sprinkle lightly with salt and pepper. No need to overthink it.
Choose your cook method:
Transfer chicken to a board and shred with two forks. Or use a hand mixer on low in a bowl — wizardry, IMO.
If the sauce is thin, simmer uncovered 5–8 minutes until glossy and slightly thick. Taste and adjust salt, vinegar, or sweetener.
Toss shredded chicken back into the sauce. It should be saucy but not soupy.
Split and lightly toast whole-grain buns until crisp at edges — better structure, better flavor.
Pile chicken high, crown with slaw or pickles, cap with bun. Take a victory lap.