• 2 ounces dried, whole New Mexico (California), guajillo, or pasilla chiles, or a combination (6 to 8 chiles)
• 1½ teaspoons ground cumin seed
• ½ teaspoon freshly ground black pepper
• 5 tablespoons lard, vegetable oil, or rendered beef suet
• 2½ pounds boneless beef chuck, well trimmed and cut into ¾-inch cubes (to yield 2 pounds after trimming)
• ⅓ cup finely chopped onion
• 3 large cloves garlic, minced
• 2 cups beef stock , or canned low-sodium beef broth, plus more as needed
• 2¼ cups water, plus more as needed
• 2 tablespoons masa harina (corn tortilla flour)
• 1 tablespoon firmly packed dark brown sugar, plus more as needed
• 1½ tablespoons distilled white vinegar, plus more as needed