Tender and juicy warm cinnamon sugar apple slices covered with a crispy and buttery brown sugar oat topping that's perfect for enjoying with vanilla ice cream! The best part of all is that you can make it using only 7 simple ingredients!
Preheat oven to 350º Fahrenheit. Peel, core, and cut the apples into thin slices. In a large bowl, toss the apple slices with the sugar, cinnamon, and 2 tablespoons flour. Combine until all the slices are evenly coated.
Pour the apples and any remaining sugar into a 9x13" baking dish. Set aside for now. (*Read Notes below for freezing instructions.)
In another bowl, mix together the brown sugar, old fashioned oats, and flour until well combined. (If you are using unsalted butter, add a pinch of salt to the topping now.)
Cut the sticks of cold butter into cubes, then add them to the bowl. Cut in the butter using a pastry knife or your hands until the mixture is nice and crumbly and there is no dry flour left.
Sprinkle the topping evenly over the apple slices in the baking dish. Bake uncovered in a preheated oven for 45 minutes or until the apples around the edges are nice and bubbly and the topping is lightly toasted golden brown.
Allow to cool for 30 minutes or so before cutting and serving. Top with vanilla ice cream and a drizzle of caramel, if desired!
Notes
* To freeze, place the ingredients into a freezer-safe 9x13" aluminum pan. Prepare the apple mixture and topping as described, but stop right before baking. Cover the dish tightly in plastic wrap, then wrap in foil. If desired, place the entire dish into a 2-gallon freezer-safe ziplock bag. Remove the air, label, and freeze. Enjoy within 3 to 4 months. Allow the apple crisp to thaw overnight in the refrigerator. Uncover completely and bake as instructed above. To bake from frozen, uncover and bake for 60 to 70 minutes or until the apples around the edge are bubbly and the top is golden brown.