1. Preheat your oven to 375 F (190 C). Lightly grease an 8×8 inch or 9×9 inch baking dish with butter or cooking spray.

2. In a large bowl, combine the sliced apples and pears. Sprinkle the granulated sugar, 1 tablespoon of all-purpose flour, ground cinnamon, and ground nutmeg over the fruit. Toss gently until all the fruit slices are evenly coated.

3. Pour the seasoned fruit mixture into your prepared baking dish, spreading it out evenly.

4. In a separate medium bowl, combine the 1/2 cup all-purpose flour, packed light brown sugar, old-fashioned rolled oats, and salt. Use a fork or your fingertips to mix these dry ingredients together.

5. Add the cold, diced butter to the dry crumble ingredients. Using your fingertips or a pastry blender, work the butter into the mixture until it resembles coarse crumbs with some pea-sized pieces remaining.

6. Sprinkle the crumble topping evenly over the fruit mixture in the baking dish. Do not press it down too firmly.

7. Place the baking dish in the preheated oven and bake for 35-40 minutes, or until the topping is golden brown and the fruit filling is bubbly around the edges.

8. Remove the crisp from the oven and let it cool on a wire rack for at least 10-15 minutes before serving.