Preparation / Directions:
Lay half the onions and peppers in a large heavy stewing pot. Add the roast, and cover with the remaining peppers. Add enough beef broth to come about halfway up the side of the roast. Cover, and cook over medium-low heat, turning the roast occasionally, until the meat is virtually falling apart (3- 4 hours). If you have a crock pot, all day (without turning) is fine.
Remove the roast from the pot, pull off and discard any remaining fat, and using a fork or your fingers, pull the lean meat into shreds. Mix in the onions/peppers and enough of the defatted cooking liquid to form a juicy, but not soupy mixture. Season to taste with salt.
This will reheat very well, or hold nicely in a chafing dish. Use as a filling for soft or hard tacos (lowest in fat would be soft tacos made with steamed or lightly heated corn tortillas).