1. Preheat oven to 350 degrees. Line 2 baking sheets with parchment paper or Silpat and set aside.
2. In a mixer, beat the butter, regular sugar and brown sugar until fluffy, about 1 minute. Beat in the egg, vanilla extract, and salt, and mix to combine.
3. Remove from mixer and fold in flour, baking soda, and oats. Once combined, fold in raisins.
4. Scoop dough into 1 inch balls, rolling between your hands to make them perfectly circle. Place on prepared baking sheets, leaving about 2 inches between each cookie.
5. Bake for 11-12 minutes. Cookies will look underdone, but they will be perfect! Allow to cool on baking sheets for 10 minutes before transferring to wire racks to cool completely.