Preparation: Using a long knife, make a lengthwise slit in the center of the thickest end of the roast to form a deep pocket, about 3” long. Pierce beef all over with the tip of the knife. Transfer beef to a large zip-top bag (or to a non-reactive container with a lid). Pour Mojo over beef; seal the bag. Refrigerate for at least 4 hours, or up to 24 hours for best results.

Preheat & Stuff: Heat oven to 275°F. Remove beef from the refrigerator at least 30 minutes before cooking; discard marinade. Using paper towels, pat beef dry. Stuff the pocket of beef with chorizo. Using kitchen twine, firmly tie beef in 1½ ” intervals, perpendicular to the pocket, to enclose the chorizo. Sprinkle beef all over with Adobo.

Searing: Heat oil in a large Dutch oven, or large oven-proof pot over medium-high heat. Add beef. Cook, flipping beef with tongs, until golden brown all over, 5-7 minutes; transfer to a plate. Add onions to the pot; cook, stirring occasionally, until soft, about 3 minutes more. Pour wine and 4 cups water into the pot. Bring the liquid to a boil, scraping up browned bits from the bottom of the pot with a wooden spoon. Add carrots, olives, bay leaves, oregano, and beef to the pot. Tightly cover the pot and transfer to the oven.

Roasting: Cook, flipping roast every hour, until beef is fork-tender, about 4 hours, adding potatoes after 3 ½ hours.

Serving: Transfer beef, potatoes, carrots, and olives to a platter; tightly cover with foil to keep warm. Place the pot on the stove over medium-high heat. Bring the liquid to a boil. Cook, stirring occasionally, until the sauce reduces to 2 cups, about 5 minutes. To serve, cut the beef roast into ½” slices. Pour sauce over beef. Serve warm.