INGREDIENTS 

• 6 tablespoons unsalted butter, divided into 2
• 1 pound beef liver, sliced ¼” thick
• 2 cups of whole milk
• Salt & pepper to taste
• ½ teaspoon ground cumin
• 1 large yellow onion, thinly sliced
• 2 garlic cloves, minced
• 1 teaspoon Worcestershire sauce
• 1 teaspoon Maggi sauce
• ¼ cup beef stock
• 1 tablespoon all-purpose flour
• 1 teaspoon tomato paste

INSTRUCTIONS

• To clean the liver, use a small knife and cut through the membrane and peel it off, and place in a bowl. Add milk and soak for about 10 minutes 
• Discard milk and rinse liver in cold water. Add salt & pepper to taste, and cumin and mix until fully incorporated. Cover and marinate for 1 hour 
• Melt 3 tablespoons of butter in a large skillet over medium-high heat. Add the liver slices and cook for 5 minutes on one side. Turn and cook for 5 minutes on the other side. Remove from the skillet and set aside (Note: be sure not to overcook, to avoid the liver becoming tough)
• Add the remaining 3 tablespoons of butter to the skillet. Once melted, add the sliced onions and cook them until caramelized, for about 5 minutes. Add garlic, Worcestershire sauce, and Maggi sauce, and stir until well combined. Reduce heat to medium and simmer for another 5 minutes
• Add 1 tablespoon of the beef stock to the tablespoon of flour and mix together in a small bowl, until it forms a paste. Add the rest of the beef stock to the paste and mix until well combined. Add the mixture to the skillet and bring to a boil
• Reduce the heat to low and stir in the tomato paste and simmer for about 5 minutes to allow the liquid to reduce by a third, and gravy has thickened slightly. Add the liver and simmer for 2-3 minutes to allow the gravy to warm the liver
• Serve immediately with Panamanian corn tortillas, Panamanian hojaldas, or over a bed of white rice

TIP

Liver is commonly soaked in vinegar or lemon juice to get rid of the smell and toxins. However, I found that milk does the same thing as vinegar or lemon juice, plus it also tenderizes the liver.