Prepare the kidney as directed for Kidney Hot Pot. Coat the slices of kidney with seasoned flour. Heat the dripping in a stewpan and fry the kidney until browned on both sides. Chop the onion finely and fry at the same time until lightly browned. Stir in any remaining flour and brown. Add the stock and ketchup and stir until boiling. Cover with a lid and simmer very gently for about 1½–2 hr. If cooked too quickly the kidney will become tough. When ready re-season if necessary and serve on a hot dish with a border of rice or mashed potato. Garnish with green peas.