Preheat the oven to 180°C. Grease a 40 x 25cm baking sheet with non-stick spray.
1. Mix the cake flour, sugar, salt and baking powder. Rub the butter into the flour mixture until the texture is like that of breadcrumbs.
2. In a separate bowl, whisk the amasi and eggs together and add to the flour mixture. Combine well, then transfer the dough to the baking sheet.