Place corned beef brisket fat side down on the counter or onto a pan with a rack.
Coat top and sides with spicy brown mustard.
Sprinkle Jeff's Texas style rub onto the top and sides of the meat
Prepare smoker for cooking at 250°F (121°C) to 275°F (135°C) using a mix of cherry and maple wood chips or whatever smoking wood you have available.
If your smoker uses a water pan, fill it up.
Place meat onto the smoker grate or you can place the pan with a rack into the smoker.
When the internal temperature of the corned beef reaches 160°F (71°C), place the meat into a foil pan covered with foil and continue to cook.
When the internal temperature reaches ~200°F (93°C), bring the meat into the house and cube it up into pieces that are about 1-inch x 1-inch. (be sure to save any rendered brisket juice that is in the pan)
Place the cubes back into the pan and pour about 1 cup of the rendered brisket juice over the cubes.Note: If you are using a pellet smoker, raise the temperature to HI otherwise use your grill or an oven on HI heat or about 500°F (260°C).
Continue cooking the pan of cubed corned beef brisket burnt ends on very high heat until they begin to darken and get crispy edges.
Coat with honey mustard dressing a time or two during this last step to expedite this process and give them another layer of flavor.
When they are finished cooking, serve immediately.