Cut the meat into bite-sized portions. Remove any tendons.
Cut the onions into bite-sized portions and remove the hard part.
Remove the skin from the kiwi and crush. Spread over the steak and leave overnight in the fridge to soften.
Remove from the fridge 30 minutes before cooking and wipe off the kiwi with kitchen paper.
Prepare pastry for the pie case using this recipe.
Melt the beef fat in a frying pan (use ordinary oil if you have none) and fry the beef and kidneys until cooked on the surface. Remove to a plate.
Roughly remove the fat from the frying pan and add the onions. Fry until they start to brown, then add the mushrooms and flour and fry briefly.
Add the red wine, ketchup, worcestor sauce, beef stock, chocolate, pepper, and nutmeg and bring to the boil over a strong heat.
Add the meat and simmer over a low heat for 30 minutes. Skim the surface occasionally.
Butter a pie dish and line with half the pastry prepared earlier (recipe).
Cool the prepared filling and pour into the pie crust.
Roll out the remaining pastry and use to cover the pie. Brush with a little egg beaten with a little milk to help the pastry brown. Decorate with pastry offcuts as you like.
Bake in a 250 degree centigrade oven for 40 minutes.