Place your salt cod into a pan of clean water and bring to the boil, then reduce to a gentle simmer for 14 minutes. Remove the fish from the water and allow to cool to a handleable heat. Remove any bones and skin (be warned—this is very sticky).
Meanwhile cook your potatoes in salted water, as if for mashing. Drain when done. In two separate pans heat the milk and oil.
First whiz your garlic and a pinch of pepper in the food processor to a fine purée (as once the other ingredients are added you will never get rid of any garlic chippings). Once this is achieved add the cod and potatoes, then have the motor running and add in equal quantities, bit by bit, the hot oil and milk until you achieve the right consistency; a giving, slightly hairy purée.
As a starter serve warm with toast and 8-minute, firmish boiled eggs. As a main course, spread thickly on toast and top with a poached egg.