Special equipment: a deep-frying thermometer
For the wings: Heat 3 inches of canola oil in a heavy pot until a deep-frying thermometer registers 375 degrees F.
Add half of the chicken pieces to the oil and fry until golden brown and fully cooked, about 5 minutes. Drain on paper towels, then repeat with the other half.
For the BBQ sauce: Heat the oil in a saucepan over medium-low heat. Add the garlic and onions and cook, stirring and watching carefully so they don't burn, about 5 minutes. Reduce the heat to low. Add the ketchup, molasses, brown sugar, chipotle peppers, vinegar (or less to taste), Worcestershire sauce and salt and stir. Bring to a simmer and cook for 20 minutes.
Preheat the oven to 325 degrees F.
Taste the sauce after simmering and add whatever ingredient it needs (more spice, more sugar, etc.). Put the wings in an ovenproof dish, pour the sauce over the top and toss to coat. Bake until the wings are heated through and the sauce is brown and bubbling, about 15 minutes.