Preheat your oven to 350ºF (180ºC) and have a 4 to 6 quart cast iron Dutch oven ready. Place the peeled, chopped apples directly into the Dutch oven. Add the lemon juice and stir to coat the apples and prevent browning. Then add the granulated sugar, 1/4 cup all-purpose flour, and 1 teaspoon ground cinnamon. Stir again to ensure the apples are well coated with the mixture. Set aside while you prepare the topping.

In a medium bowl, combine 1/2 cup all-purpose flour, packed brown sugar, rolled oats, 1 teaspoon ground cinnamon, and salt. Stir well to thoroughly mix the dry ingredients together. This forms the base of your crisp topping.

Add the butter to the bowl with the oat mixture. Using your hands or a fork, work the butter into the dry ingredients until everything is well combined and the mixture resembles a soft, chunky dough. I find that using my fingers helps incorporate the butter more evenly for a perfect crumbly texture.

Scatter the oat topping from Step 3 evenly in chunks over the prepared apple filling in the Dutch oven. Place the Dutch oven in the preheated oven, uncovered. Bake for 55 to 60 minutes, or until the topping is golden brown and the filling is bubbling up around the edges.

Remove the apple crisp from the oven and let it cool on a wire rack for 10 minutes before serving. Serve warm, ideally with a scoop of vanilla ice cream or a dollop of whipped cream for an extra-special touch. I love to enjoy the crisp while it's still a bit warm—the combination with cold ice cream is just unbeatable!