In a very large nonstick skillet, heat 1 tablespoon of the canola oil. Add the shallots and garlic and stir-fry over moderately high heat until lightly browned, about 2 minutes. Add the ground pork, brown sugar, black bean sauce, dried chiles, Maggi sauce and fish sauce and cook, breaking up the meat with a spoon, until it is browned in spots, about 10 minutes. Add 3/4 cup of the chicken broth and cook over moderately low heat until the broth has evaporated, about 8 minutes. Stir in 1 tablespoon of the vinegar. Transfer the ground pork mixture to a bowl and wipe out the skillet.