Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a mixing bowl, combine the flour, baking soda, baking powder, ground cinnamon, ground nutmeg, and salt. Stir until well mixed and set aside.

In a separate large bowl, beat the softened butter, brown sugar, and granulated sugar until light and fluffy, about 3 to 4 minutes.

Add in one large egg and the teaspoon of vanilla extract, mixing until incorporated.

Gradually add the dry ingredients to the wet mixture, mixing just until combined.

Gently fold in the diced fresh apples and oats.

In a small bowl, mix together the flour, brown sugar, softened butter, and cinnamon to create the crumb topping.

Break the mixture down until it resembles coarse crumbs.

Drop spoonfuls of dough onto your prepared baking sheet, leaving space between each cookie.

Sprinkle a generous amount of crumb topping over each cookie.

Bake for 12 to 15 minutes, or until the edges turn golden brown. Keep an eye on them.

Allow cookies to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.