First, preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper. Prepare all ingredients by measuring accurately to set yourself up for success. In a mixing bowl, cream the softened butter and brown sugar until light and fluffy, enhancing the texture of your oatmeal raisin cookies.

Beat in the eggs one at a time, ensuring each is fully incorporated for a uniform dough. Add vanilla and molasses, mixing on high until combined, which helps build that deep flavor. In a separate bowl, whisk together the all-purpose flour, baking soda, cinnamon, and salt to evenly distribute leavening and spices.

Gradually add the dry ingredients to the wet mixture, mixing until just combined to avoid tough cookies. Fold in the rolled oats and raisins carefully to retain their texture and ensure even distribution. For vegan or gluten-free adaptations, substitute eggs and flour at this stage to maintain proper dough consistency.

Scoop tablespoon-sized portions onto the prepared baking sheet, spacing them about 2 inches apart. Bake for 10-12 minutes until the edges turn golden but the centers remain soft, perfect for chewy oatmeal raisin cookies. Allow cookies to cool on the tray for 5 minutes before transferring to a wire rack to finish cooling, as this helps them set without becoming brittle.