Preheat your oven to 375°F (190°C). Grease a 9x13 inch baking dish and set aside.

In a large mixing bowl, toss the sliced apples with lemon juice to prevent them from browning.

In a separate bowl, mix together the granulated sugar, cinnamon, and nutmeg. Pour this mixture over the apples and toss until the apples are evenly coated.

Spread the coated apple slices evenly in the prepared baking dish.

In the same bowl used for the sugar mixture (to save dishes), combine the flour, oats, brown sugar, and salt. Mix well.

Add the cold butter pieces to the flour mixture. Using your fingers or a pastry cutter, work the butter into the dry ingredients until the mixture resembles coarse crumbs.

Sprinkle the crumb mixture evenly over the apples in the baking dish.

Bake in the preheated oven for 35-40 minutes, or until the topping is golden brown and the apples are tender and bubbling.

Remove from the oven and let cool slightly before serving.

Serve warm, topped with vanilla ice cream or whipped cream if desired.

Enjoy your delicious homemade apple crisp!