In a large bowl, toss together apples, lemon juice, and sugar.
Melt butter in a large oven-safe skillet over medium heat. Add apples and cook for 5 minutes, stirring occasionally. Remove from heat.
Meanwhile, make the topping by combining flour, oats, brown sugar, and salt in a large bowl. Add the butter to the bowl and then mix until crumbly, using clean hands if necessary.
Scatter the topping over the apples, and bake for 35 to 40 minutes. Let cool slightly before serving.
Notes
Variations
Apple Crisp with No Flour Want to make an apple crisp with no flour? Substitute almond meal for the gluten-free flour.
Sugar-Free Apple Crisp For a sugar-free apple crisp, use Swerve sweetener.