01 - Set oven temperature to 350°F (175°C) and lightly grease a 9-inch baking dish.
02 - In a large mixing bowl, combine sliced apples, lemon juice, granulated sugar, ground cinnamon, ground nutmeg, and all-purpose flour. Stir until apples are evenly coated, then arrange the mixture in the prepared dish.
03 - In a separate bowl, blend rolled oats, all-purpose flour, light brown sugar, and salt. Incorporate diced cold butter using a pastry cutter or fork until the mixture forms coarse crumbs. Fold in the chopped pecans.
04 - Distribute the topping evenly over the apple mixture. Bake for 35 to 40 minutes, or until the topping turns golden brown and apples become bubbling and tender.
05 - Allow the crisp to cool slightly before serving. Present warm, optionally accompanied by vanilla ice cream or whipped cream.