Dr. Pepper Pulled Pork

Name: Dr. Pepper Pulled Pork
Prep time: 5 min
Cook time: 240 min
Ingredients: 5 lb. pork shoulder or butt; 1 onion (coarsely chopped); 11 oz. chipotle peppers in adobo sauce; 24 fl. oz. Dr. Pepper; 2 Tbsp. brown sugar; 1/4 tsp. salt; 1/2 tsp. pepper; 1 large (gallon) freezer bag or reusable silicone bag