Lengua Estofado a Rich and Tender Braised Beef Tongue

Place the beef tongue in a large stockpot. Cover with water. Add onion quarters, garlic cloves, bay leaves, peppercorns, and salt. Bring to a boil, then reduce heat and simmer for 2-3 hours, or until the tongue is very tender when pierced with a fork.

Remove the tongue from the pot and let it cool slightly. Once cool enough to handle, peel off the tough outer skin. Slice the tongue into 1/4-inch thick slices.

In a large pot or Dutch oven, heat olive oil over medium heat. Add chopped onion and garlic and sauté until softened and fragrant. Add the red and green bell peppers and cook until slightly softened.

Stir in the tomato sauce, tomato paste, beef broth, and red wine (if using). Bring to a simmer.

Add the sliced beef tongue, olives, mushrooms, soy sauce, and sugar to the sauce. Season with salt and pepper to taste. Reduce heat to low, cover, and simmer for 2-2.5 hours, or until the sauce has thickened and the tongue is very tender.

In a small bowl, whisk together cornstarch and water to create a slurry. Slowly add the slurry to the stew, stirring constantly, until the sauce thickens to your desired consistency.

Garnish with chopped fresh parsley and serve hot.