Heat the oil in a deep, heavy saucepan to about 360 F, or until a cube of bread browns in about 30 seconds.
Shape the cold macaroni and cheese into small balls.
In a shallow bowl, beat the eggs lightly with 2 tablespoons of milk.
Dip the mac and cheese balls in bread crumbs, then into the beaten eggs, then in crumbs again.
Drop carefully into hot fat and cook, turning, until golden brown, about 1 to 2 minutes.
Remove to paper towels to drain; keep warm while making subsequent batches.