Season the beef chuck roast with salt and black pepper on all sides.
In a large skillet, heat the olive oil over medium-high heat. Sear the roast for about 3-4 minutes on each side until browned. Transfer the roast to the crockpot.
In the same skillet, add the diced onion and garlic, sautéing for 2-3 minutes until softened.
Pour in the beef broth, then add the pineapple chunks, chipotle in adobo sauce, soy sauce, brown sugar, cumin, and smoked paprika. Stir to combine.
Pour the mixture over the roast in the crockpot. Cover and cook on low for 8 hours or on high for 4 hours, until the meat is tender and easily shreds with a fork.
Once cooked, shred the beef with two forks and mix it with the sauce in the crockpot.
To serve, place a scoop of cooked rice in a bowl, top with the shredded pot roast, and garnish with avocado slices and fresh cilantro. Serve with lime wedges on the side.