Prepare the chili base by heating olive oil over medium-high heat in a cast-iron Dutch oven. Sauté onions and bell peppers until translucent. Add garlic and sauté for 1-2 minutes more, until garlic is fragrant but not browned.
Add chili powder, garlic powder, crushed tomatoes, diced tomatoes, and kidney beans. Stir and set aside.
Combine ground beef, Worcestershire sauce, salt, pepper, and Montreal steak seasoning in a large mixing bowl.
Gently form the ground beef mixture into a loaf. You want it to be solid but not packed.
Preheat your Z Grills pellet smoker to 300°F.
Once the grill is preheated, place the Dutch oven (with the chili base inside of it) uncovered directly on the grill grate.
Place a grill rack over the Dutch oven.
Place the seasoned ground beef loaf on top of the grill rack, so that the juices from the beef drip into the Dutch oven as it cooks.
Cook until the internal temperature of the ground beef loaf reaches 145°F, about 2 hours.
Break up the beef with tongs, allowing it to fall through the grate into the chili base.
When all of the beef is crumbled into the chili, cook for an additional 2 hours.
Remove chili from heat and stir in the cocoa powder. This is optional to bring out the flavors of the chili.