Preheat your oven: Set your oven to 350°F (175°C). Grease a 9x13-inch baking dish or similar-sized pan.
Prepare the filling: In a large mixing bowl, combine the apple chunks with brown sugar, flour, vanilla extract, cinnamon, nutmeg, and salt. Toss until the apples are evenly coated. Transfer the mixture to the prepared baking dish.
Make the topping: In a separate bowl, mix the flour, brown sugar, and cinnamon. Add the cold, cubed butter and use a pastry cutter or your fingers to mix until crumbly. Stir in the oats.
Assemble the crisp: Sprinkle the topping mixture evenly over the apples in the baking dish.
Bake: Place the dish in the oven and bake for 45-50 minutes, or until the topping is golden brown and the apple filling is bubbling.
Cool and serve: Allow the apple crisp to cool for at least 10 minutes before serving. For extra indulgence, drizzle with salted caramel or top with a scoop of vanilla ice cream.