To a saucepan, add the honey, ketchup, soy sauce, garlic, and mustard, and bring to a boil. Simmer, stirring frequently, until the sauce starts to thicken, about 10 minutes.
Add the pork tenderloin to a greased slow cooker and pour the sauce over the top. Cook on LOW for 5-6 hours, or until pork is cooked through.
Shred pork in the slow cooker and stir well to coat with the sauce. Serve with rice or mashed potatoes. Enjoy!