Baked fruit crumbles (which use fewer ingredients than standard puff pastry) first appeared during World War II due to shortages of common baking ingredients such as butter and flour . When mixing the crumble, first make sure the butter is fully incorporated into the dry ingredients. Then, using your hands, make lumps of different sizes, from peas to he quarters. Remember to cool the crumble before layering it on top of the filling. This allows the gluten to rest, the butter to solidify, and ensures a soft and delicious topping.
The recipe for Strawberry Almond Crumble Pie is available at: Country life.