Preheat your oven to 350°F. Lightly butter an 8x8-inch baking dish and set it aside. This simple apple crisp family recipe comes together quickly once your prep is complete.
Combine the peeled, sliced apples with granulated sugar, brown sugar, flour, vanilla extract, cinnamon, and nutmeg in a large bowl. Toss gently until every apple slice is evenly coated with the spiced mixture. The apples should release their juices slightly as you mix.
Spread the apple filling evenly into your prepared baking dish. Pack it down lightly so the fruit fills the bottom layer completely. The filling should feel slightly moist but not soupy.
In a separate bowl, combine old-fashioned oats, flour, softened butter, brown sugar, and salt. Use a fork or your fingers to mix until the topping resembles coarse breadcrumbs with pea-sized butter pieces throughout. Sprinkle the oat mixture evenly over the apple filling, pressing gently so it adheres.
Bake for 35 minutes until the topping turns golden-brown and the apple filling bubbles slightly at the edges. The thanksgiving apple crisp family recipe will smell absolutely incredible as it bakes. Let it cool for 5 minutes before serving.