Take one lamb's brain, or one-half of a calf's brain, put it in a
saucepan with cold water, change the water from time to time for a
couple of hours, until the brains are thoroughly cleansed. Then put
them in another saucepan with fresh water, and with several pieces of
onion, a little salt, a little vinegar (one tablespoon to each brain),
and some parsley stems. As soon as the water boils, take the saucepan
off, remove the brains, and put them onto a napkin. Cut them into four
pieces, put these pieces onto a plate, and season with a little
olive-oil, some lemon juice, and chopped parsley. When you are ready
to fry, roll in flour, dip in egg, and fry the brain over a moderate
fire for seven or eight minutes in olive-oil, lard, or butter.
Source:
Simple Italian Cookery 
