Heat your pot: Start by heating a Dutch oven or large heavy-bottomed pot over high heat. Add 2 tablespoons vegetable oil.
Prepare the beef: Generously season 2–3 pounds chuck roast on all sides with 2 teaspoons salt and 1 teaspoon black pepper. Carefully move the meat to the heated pot.
Sear the meat: Sear the roast for 3 minutes per side until a dark, flavorful crust forms. Use two forks or heavy-duty tongs to flip the meat. Once seared, remove the beef to a plate and discard excess cooking oil.
Make the sauce base: In a small saucepan over medium-high heat, add 2 tablespoons vegetable oil. Once hot, whisk in 3 tablespoons all-purpose flour and cook 1–2 minutes, stirring constantly until lightly golden.
Add liquids and peppers: Slowly pour in 2 ½ cups chicken stock, 1 tablespoon apple cider vinegar, 4 tablespoons tomato paste, and 2 roasted red peppers, pureed. Whisk until smooth.
Season the sauce: Add 1 teaspoon cayenne, ½ teaspoon cumin, ½ teaspoon smoked paprika, 2 tablespoons brown sugar, 3 tablespoons chili powder, ½ teaspoon cinnamon, 1 teaspoon garlic powder, 1 teaspoon onion powder, and additional salt & pepper to taste. Whisk until fully incorporated.
Simmer the sauce: Bring the sauce to a low boil, then reduce heat to low. Let it simmer for 15 minutes, stirring occasionally, until slightly thickened.
Combine with beef: Return the seared chuck roast to the Dutch oven (or transfer everything to a slow cooker). Pour the prepared sauce over the beef.
Low and slow cooking: Cover and cook on low heat for 8–10 hours, or until the beef is tender and falling-apart.
Serve: Once cooked, use two forks to pull and shred the meat. You can do this while the meat is still in the slow cooker or remove and shred on a cutting board (to get rid of any leftover fatty parts) and then return to the sauce. Toss with cooked black-and-white striped bowtie pasta. Pour extra sauce over the top and serve with a sprinkle of parsley or Parmesan if desired.