01 - Set oven to 350°F and line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together flour, oats, baking soda, salt, ginger, cinnamon, nutmeg, and cloves.
03 - Using an electric mixer or whisk, beat the butter, brown sugar, and granulated sugar until fluffy.
04 - Add eggs one at a time, mixing thoroughly after each; then blend in vanilla extract and molasses.
05 - Gradually add dry mixture to wet ingredients, stirring until just combined.
06 - Gently fold in raisins and walnuts if using.
07 - Drop tablespoon-sized portions of dough onto prepared baking sheets, spacing about 2 inches apart.
08 - Bake for 11 to 13 minutes until edges turn golden and centers are set.
09 - Allow cookies to cool on sheets for 5 minutes before transferring to a wire rack to cool completely.