Preheat pellet grill to 250°F, cube up and season roast, and use meat probe in cubes of chuck roast to track internal temperature.
Once they reach between 160-180°F, remove and place into a cast iron skillet and throw in butter, BBQ sauce, and pickle juice. Cover with tin foil and back in the smoker until they reach 200-210°F internal. Let rest for about 20-30 mins.
Prepare the pineapple salsa by dicing everything up and throwing into a bowl. Give it all a mix, shred the beef, and build the taco. Garnish with crushed chive and onion potato chips.
