In a pan, melt 100g butter then add chopped onion and fry it at medium heat around 5min by mixing from time to time.
2
Wash the liver, cut it in pieces, put it in the pan, put the lid on the pan and fry it around 10min by mixing occasionally.
3
After 10min, take off the lid and let all the juice boil completely then add salt and pepper and let it cool down.
4
After cooking down, blend the liver. In a bowl, mix the remaining 150g butter until becomes foamy and add little by little blend liver into the mixture and mix continuously.