6 cups sliced apples (about 6 medium apples, peeled and sliced 1/4 inch thick) 1 tablespoon lemon juice 3/4 cup brown sugar 1/2 cup old-fashioned oats 1/2 cup all-purpose flour 1/4 teaspoon cinnamon 1/4 teaspoon nutmeg 1/8 teaspoon salt 8 tablespoons (1 stick) cold butter, cut into pieces
Preheat the oven to 375°F. Grease an 8-inch square baking dish with butter or non-stick cooking spray.
Place the sliced apples in a large bowl and toss with the lemon juice. Add 1/4 cup of the brown sugar and toss again. Pour the apples into the prepared baking dish.
In the same bowl, mix together the remaining 1/2 cup brown sugar, oats, flour, cinnamon, nutmeg and salt. Use a pastry blender or two knives to cut in the cold butter until mixture forms coarse crumbs.
Sprinkle the oat topping evenly over the apples.
Bake for 35-40 minutes, until the apples are tender and topping is crisp and golden brown.
Serve warm with vanilla ice cream or whipped cream, if desired.