Peel, quarter and de-seed the apples cut into chunks
Wash the rhubarb and cut into 6 cm lengths, place together into a heavy based pot and add the sugar.
Cover with a lid and place over a low flame. As the fruit begins to soften and release water turn up the heat to a simmer and cook for 15 minutes. Remove from the pan and cool.
To make the crumble. Roughly rub the butter into the flour and add the other dry ingredients. Place onto a tray and bake for 6 minutes or until lightly golden, cool and reserve.
Butter a soufflé dish, making sure all areas of the interior are smeared lightly. Sprinkle with sugar and tap out excess.
Whip the egg whites with a little castor sugar until soft and peaky add the remaining sugar and beat for a further minute.
Fold one third of the egg whites into the fruit puree, incorporate thoroughly and then fold the final two thirds of egg white to lighten the mix.
Place a spoonful of the fruit puree into the soufflé mould and then spoon the soufflé mixture on top.
Sprinkle with crumble mixture. Bake in a moderate oven, preferably fan forced at 180C until risen approx 8 minutes.
