Barbacoa

1 3-4 lb chuck roast Rub 1 tablespoon black pepper 1 tablespoon oregano 1 tablespoon chili powder 2 teaspoons garlic powder 1 ½ teaspoon kosher salt Simmer sauce 2 dried guajillo chilies 2 dried ancho chilies ½ 7-oz. can chipotle peppers in adobo 3 tablespoons olive oil 1 cup chopped celery 2 cups chopped onion […]