Finely chop the potatoes and crush slightly. In a frying pan melt half the fat and lightly fry the onion. Mix in the potato and greens and season well. Add more dripping or lard. Press the bubble into the hot fat and fry over a moderate heat until browned underneath. Turn the bubble over, add the last of the fat and fry until the other side is browned.
Recipe courtesy of Jennifer Paterson and Clarissa Dickson Wright