Ingredients
Method
1.Preheat oven to 180°C (160°C fan-forced). Grease and line a deep 26x16cm (base measurement) slice pan with baking paper, extending paper at long sides for handles.
2.Combine yeast, caster sugar and 1/2 cup warm water in a small bowl; stand for 10 minutes or until frothy.
3.Using an electric mixer, beat butter and brown sugar in a medium bowl until light and creamy. Add, in 2 batches, self-raising flour and yeast mixture.
4.Add sour cream and half the cinnamon. Fold in pie apple. Spread in prepared pan. Finely chop extra pie apple, then spread evenly over top.
5.Place plain flour, extra caster sugar, remaining cinnamon and extra butter in a small bowl. Rub in butter to make coarse crumbs. Sprinkle evenly over mixture in pan.
6.Bake for 45 minutes or until a skewer inserted at centre comes out clean. Remove from oven. Stand in pan for 10 minutes; turn onto a wire rack, right-side up. Cool. Cut into squares. Serve squares dusted with icing sugar.