01 -
Preheat oven to 175°C. Lightly grease a 23x23 cm baking dish with butter or non-stick spray.
02 -
In a large mixing bowl, combine sliced apples, brown sugar, lemon juice, ground cinnamon, nutmeg, vanilla extract, and a pinch of salt. Mix thoroughly to evenly coat apples, then transfer mixture to prepared baking dish, spreading evenly.
03 -
In a separate bowl, blend oats, flour, brown sugar, baking powder, salt, and cinnamon. Incorporate cold butter using a pastry cutter or fingertips until mixture forms coarse crumbs.
04 -
Distribute the crumble topping evenly over the apple filling. Bake for 35 to 40 minutes, or until the apples bubble and the topping is golden brown.
05 -
Remove from oven and allow to cool slightly. Serve warm, accompanied by vanilla ice cream or whipped cream if desired.