When ready to cook, start the Traeger grill on smoke with lid open until fire is established (4 to 5 minutes). Set the temperature to Smoke and preheat, lid closed, for 10 to 15 minutes.
Make 1/2 inch thick hamburger patties from the meat and put on the grill. Cook for about 30 minutes. This will add a smoky flavor, but not cook them all the way through. Remove from grill and set aside.
Adjust temperature to High and place a cast iron skillet on grill. Close the lid and allow to preheat for 10 to 15 minutes.
Add oil to pan along with the onion, carrot and bell pepper. When the onions are translucent add the garlic, ancho powder, chipotle powder, salt and black pepper. Stir and cook for 5 minutes.
Add the barbecue sauce and Worcestershire and let it thicken.
Add the smoked meat, close the lid and cook for about 15 minutes. You want to just cook the meat through and coat it with sauce.
When it is the right thickness, check the taste and adjust any of the ingredients to your preference.
Toast the buns on grill if desired for 1 minute. Spoon the mixture onto the buns and serve with your favorite sides. Enjoy!