Beef and Chipotle Burritos

1 1/2 lb's boneless beef round steak cut 3/4 inch thick
1 14 1/2 oz can diced tomatoes, undrained
1/3 c chopped onion
1-2 canned chipotle peppers in adobo sauce (just 1-2 peppers, not 2 cans)
1 tsp oregano
1/4 tsp ground cumin
1 clove garlic, minced
6-8 tortillas
3/4 c shredded cheddar cheese
Pico de gallo (optional)
Sour cream (optional)

In 4 quart crock pot, add meat, tomatoes with juice, onion, peppers, seasonings, and garlic. Cover ans cook on low heat for 8-10 hours or on high heat for 4-5 hours. Remove meat from cooker and add the juices to it until you have desired consistency. Place in tortillas and serve with pico de gallo, cheese, and sour cream