Clean the liver from its skin and sinew. Chop it into medium size pieces and let them sit in the fridge for 8 hours. Take the pieces onto a cutting platter and slice them into thin layers. (like a large thinner juliening) Drain the pieces and dry them with a paper towel. Put the flour and salt into a mixing bowl, add the liver pieces. Mix the until all the pieces are covered with flour. Pour the oil in a large and deep frying pot and heat. Put the covered pieces into oil and fry for 2-3 minutes. Serve with onion and tomato slices.
Bon Appetite!