Mustard pie

Preheat the oven to 180 ºC (350 ºF). Grease a 1,5 litre ovenproof dish with margarine. Combine the mince and breadcrumbs. Beat the egg yolks lightly and add to the meat mixture. Add the green pepper, onion, tomato purée, horseradish sauce, salt and sugar. Blend the mustard powder with a little water to form a paste and add half the mixture to the meat mixture. Mix well and spoon into the prepared dish. Bake for about half an hour or until pale brown. Beat the egg white and cream of tartar until stiff and add the remaining prepared mustard. Beat until well blended and spread on top of the meat mixture. Return to the oven and bake until the topping is golden brown.
Serves 4-6.