01 - Preheat the oven to 350°F. Line two baking sheets with parchment paper.
02 - Whisk together flour, baking soda, salt, ground cinnamon, and ground nutmeg in a medium bowl.
03 - In a large bowl, beat together softened butter, light brown sugar, and granulated sugar until light and creamy.
04 - Add eggs one at a time, mixing thoroughly after each addition. Stir in vanilla extract.
05 - Gradually add dry ingredients to the wet mixture, mixing until just incorporated.
06 - With a spatula, fold in rolled oats, raisins, diced apple, and nuts if using until the mixture is evenly distributed.
07 - Drop heaping tablespoons of dough onto the prepared baking sheets, spacing each portion 2 inches apart.
08 - Bake for 12 to 14 minutes or until edges are golden and centers appear set.
09 - Let the cookies cool on baking sheets for 5 minutes, then transfer to a wire rack to cool completely.