- 1 tablespoon avocado oil
 - 2 pounds beef sirloin tip roast
 - 1 (28 ounce) can fire-roasted diced tomatoes, drained
 - 1 cup beef broth
 - 2 onions, sliced
 - 3 bell peppers, seeded and sliced into strips
 - 1 (6 ounce) can tomato paste
 - 2 tablespoons minced garlic
 - 1 tablespoon olive oil
 - 1 tablespoon red wine vinegar
 - 1 teaspoon ground cumin
 - 1 teaspoon salt
 - 1/4 cup chopped fresh cilantro
 
- Heat avocado oil in a large skillet over medium-high heat; cook beef roast in the hot oil until browned, about 4 minutes per side. Transfer roast to a slow cooker. Pour tomatoes and beef broth over roast; add onions and bell peppers.
 - Mix tomato paste, garlic, olive oil, vinegar, cumin, and salt together in a bowl; pour over onions and bell peppers.
 - Cook on High for 1 hour. Decrease heat to Low and cook until beef is tender enough to shred, about 8 hours.
 - Remove beef from slow cooker and shred on a work surface using 2 forks. Return shredded beef to slow cooker; add cilantro and stir.
 - Cook on Low for 1 hour more.