(This recipe works great for pork and venison, too.)
1 T. black pepper
1 T. paprika
2 t. chili powder
1/2 t. salt
1/2 t. cayenne pepper
1/2 t. garlic powder or 2 cloves minced garlic
1/4 t. mustard powder
1/2 - 1 c. beef broth or water
Rub meat with mixture, cook in slow cooker on LOW for 6-8 hours.
