01 - Preheat the oven to 350°F. Line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together the flour, baking soda, salt, cinnamon, nutmeg, and ginger. Set aside.
03 - In a large bowl, cream the softened butter, brown sugar, and granulated sugar together until light and fluffy, about 2 minutes.
04 - Beat in the eggs one at a time, then add the vanilla extract and orange zest if using, mixing until combined.
05 - Gradually add the dry ingredients to the wet mixture, mixing just until incorporated.
06 - Stir in the oats, raisins, and walnuts if using with a spatula until evenly distributed.
07 - Drop rounded tablespoons of dough (about 2 tablespoons per cookie) onto the prepared baking sheets, spacing about 2 inches apart.
08 - Bake for 10-12 minutes, or until the edges are lightly golden and the centers look just set.
09 - Cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.