01 -
Get your oven nice and hot at 350°F (175°C). Grab a 9x13 baking dish and give it a light coating of baking spray.
02 -
In a big bowl, toss your sliced apples with brown sugar, flour, white sugar, cinnamon, nutmeg, and vanilla until every slice is coated in that sweet, spicy goodness.
03 -
Spread your spiced apples in the baking dish, making sure they're even but not packed down too tight - we want those juices to bubble up!
04 -
Mix your oats, flour, brown sugar, cinnamon, salt, and baking powder in a bowl. Pour in that melted butter and stir until you've got a nice crumbly mixture with no dry spots.
05 -
Sprinkle your crumbly topping all over those apples, making sure every bit is covered.
06 -
Pop it in the oven, uncovered, and let it bake for about 40-45 minutes. You'll know it's done when the top is golden brown and you can see those apple juices bubbling up around the edges.
07 -
Let it rest for 5-10 minutes - this helps the filling thicken up and makes it easier to serve. Perfect with a scoop of vanilla ice cream!