Step 1: Preheat the Oven

• Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper to prevent sticking.

Step 2: Prepare the Dry Ingredients

• In a medium bowl, whisk together the flour, baking soda, salt, cinnamon, and nutmeg. Set aside.

Step 3: Cream the Butter and Sugars

• In a large mixing bowl, beat the butter, brown sugar, and granulated sugar until light and fluffy. This step takes about 2-3 minutes using an electric mixer or a whisk.

Step 4: Add the Wet Ingredients

• Beat in the egg and vanilla extract until fully combined.

Step 5: Incorporate the Dry Ingredients

• Gradually mix the dry ingredients into the wet mixture, stirring until just combined.

Step 6: Fold in Oats, Apples, and Add-ins

• Gently fold in the rolled oats, diced apples, nuts, and raisins (if using).

Step 7: Scoop the Dough

• Use a cookie scoop or a spoon to drop tablespoon-sized portions of dough onto the prepared baking sheet, spacing them about 2 inches apart.

Step 8: Bake the Cookies

• Bake for 10-12 minutes, or until the edges are golden brown and the centers look set.

Step 9: Cool the Cookies

• Allow the cookies to cool on the baking sheet for 5 minutes, then transfer them to a cooling rack to cool completely.