Step 1

Heat vegetable oil in large skillet over medium heat. Brown chuck roast on both sides; place in large slow cooker.

Step 2

Add garlic, chipotle peppers, cumin, onion powder, oregano, cloves, salt, pepper, vinegar, beef broth and lime juice to food processor.  Pulse several times to blend and pour over chuck roast.

Step 3

Cover the slow cooker; cook on low for 8 hours or high for 5-6 or until fork tender.

Step 4

Using a couple of forks shred chuck roast right in slow cooker removing any fat or gristle.  Spoon meat into soft taco shells and top with lettuce, tomato, red onion and avocado.  Serve promptly.