Crock Pot Burrito Meat

Name: Crock Pot Burrito Meat
Ingredients: 5 lbs beef roast (chicken can be substituted ) or 5 lbs pork roast, fat trimmed (chicken can be substituted ); 4 -5 boneless skinless chicken breasts or 1 (4 -5 lb) roasting chickens; 1 small onion, chopped; 1⁄2 cup celery, chopped; 1⁄2 cup water; 1 dash salt; 1 tablespoon black pepper; 1 tablespoon garlic powder; 1 tablespoon cumin; 1 tablespoon chili powder (or one envelope taco seasoning); OPTIONAL; sour cream (optional); salsa (optional); shredded lettuce (optional); shredded cheese (optional); chopped tomato (optional); guacamole (optional); chopped onion (optional); chopped cilantro (optional)