Light a full chimney of charcoal. When the coals are ashed over, dump them on one side of the grill to make a hot zone. Leave the other side empty for the indirect heat (cool zone). Close the lid and adjust vents to maintain a temperature of around 225-250°F.
Gas Grill: Turn on one side of your burners to medium heat leaving the other side off. Close the lid and preheat the grill to about 225-250°F.
Add an aluminum pan filled with water to the grill to help maintain moisture in the cooking environment and stabilize the temperature, which prevents the meat from drying out during the long cooking process.
Cut the beef chuck roast into 1.5-inch cubes. Try to keep them at the same size so they cook evenly. Sprinkle the BBQ rub all over until every cube is well coated.
Place the cubes on the cool side of your grill (indirect heat). Close the lid and smoke the meat at 225-250°F for 2 hours. Check to see that the meat has a dark, smoky crust and reads about 160–170°F internally with a meat thermometer.
Pro tip: I placed them on a cookie rack and then on the grill grates to keep them from falling into the grill.
Move the meat cubes into an aluminum foil pan. Add about 5 tablespoons butter, ¼ cup honey, and ½ cup or more of BBQ sauce. Cover the pan tightly with aluminum foil and return it to the cool side of the grill. Continue cooking for another 1.5 to 2 hours, or until the meat is probe tender and its internal temperature reads 200–205°F inside.
Take the pan off the grill and let it rest (still covered) for 20 to 30 minutes. This helps the juices settle and keeps the meat tender. Uncover the pan and gently stir the meat with the juices.
For extra glaze, add a final layer of BBQ sauce and return to the grill for 5-10 minutes uncovered. Serve the burnt ends hot, straight from the pan! These burnt ends are delicious with coleslaw, mac and cheese, or piled into a sandwich.