Preheat the Oven — Heat your oven to 350°F (175°C). Line two baking sheets with parchment paper or silicone baking mats and set aside.
Mix the Dry Ingredients — In a medium bowl, whisk together the flour, rolled oats, baking soda, cinnamon, and salt until evenly combined.
Cream the Butter and Sugars — In a large bowl, beat the softened butter with the brown sugar and granulated sugar for 2–3 minutes until the mixture is light and fluffy.
Add Eggs and Vanilla — Beat in the eggs one at a time, then mix in the vanilla extract until everything is smooth and fully incorporated.
Combine the Dough — Gradually stir the dry ingredient mixture into the wet ingredients until just combined. Fold in the soaked, patted-dry raisins until evenly distributed. Do not overmix.
Scoop the Dough — Use a cookie scoop or tablespoon to portion the dough onto the prepared baking sheets, spacing each about 2 inches apart.
Bake — Bake for 10–12 minutes, until the edges are lightly golden and the centers still look slightly underdone. Do not overbake.
Cool — Let the cookies rest on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely. They will firm up as they cool.