One of the most typical liver recipes in Portugal. Simple to make and tastes amazing.  

Ingredients

• 4 steaks of beef liver
• 2 cloves garlic, sliced
• 2 onions, sliced
• 1 bay leaf
• 50 ml white wine vinegar
• 100 ml white wine
• Salt and pepper, to taste
• Lard, as needed
• Chopped parsley, to taste

Instructions
Start by cutting the liver steaks into thin strips. Then season it with salt, pepper, garlic, bay leaf, vinegar and white wine. Let it marinate for at least 3 hours. 
Melt the lard in a frying pan. Remove the liver from the marinade (reserve the liquid for later). To the frying pan, add the garlic and bay leaf from the marinade and the liver. Fry the liver very quickly because it cooks very fast and when overcooked it becomes hard. Tip: when it changes colour on the outside and there’s no blood traces inside, it’s ready 
Remove the liver from the pan and set aside in a warm place. 
In the same frying pan where you fried the liver, fry the sliced ​​onions – if necessary add a bit of olive oil. Season the onion with a little salt and let it soften, stirring occasionally. When the onion is cooked, add the marinade from the liver liver and boil for 5 /10 min over low heat. 
Add the reserved liver to the onion, add chopped parsley and stir to combine the ingredients. Remove from heat immediately so you don’t overcook the liver. 
Serve with mashed potatoes.