Heat the oven to 350 degrees F and arrange a rack in the middle.
Mix together Mista Brown's Original Jerk Sauce, sherry, beef broth and brown sugar until evenly combined; set aside. Pat roast dry with a paper towel and season well with salt and pepper.
Place a 3-quart Dutch oven or other heavy-bottomed, shallow pot with a tight-fitting lid over medium heat and add oil. When oil starts to smoke, add roast and sear until well browned, about 2 minutes per side.
Remove roast to a plate and set aside. And add garlic and ginger and cook just until fragrant, about 30 seconds. Stir in Mista Brown's Authentic Jerk Sauce mixture and bring to a simmer.
Return roast to pan and bring to a simmer.
Cover and transfer to oven to cook, turning occasionally, until meat is knife tender enough to shred, about 3 hours. The time will depend on the thickness of your roast. (For quicker cooking time, cut roast in half.)
Remove pot from oven. Remove roast from pot and place on platter to shred. Set aside until later.
Place pot with cooking liquid on stovetop and cook on high heat, uncovered, until the liquid is reduced by half. This is the sauce. Strain sauce and add a cup at a time to shredded beef, mixing thoroughly for heat preference. The more liquid you add, the spicier it will be!
Serve on Coco bread if available or Hawaiian Rolls.
*Note: Leaving to run some errands? In Step 6, transfer to crock pot and cook on high 4-5 hours or low 6-8 hours. Depends on thickness of beef.
**Substitute: Boneless Beef Chuck Roast for a more decadent sandwich. Adjust time as needed until meat is tender enough to shred.