Preheat oven to 375 degrees and lightly grease a 9×9 baking dish.
Add apples to a large bowl or plastic bag and sprinkle with lemon juice. Toss to coat with granulated sugar, cornstarch, cinnamon, and salt.
Transfer to baking dish and set aside.
Rinse and dry bowl and add brown sugar, flour, almond meal, oats, cinnamon and stir. Add melted butter and mix until it resembles wet sand.
Sprinkle topping over the apples and bake until apples are soft and topping is golden brown (between 45 minutes to 1 hour).
Let rest 10-15 minutes before serving.
It’s great with vanilla ice cream and caramel sauce is also a lovely addition.