Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a medium bowl, combine the rolled oats, gluten-free all-purpose flour, baking soda, salt, and ground cinnamon.
In a large mixing bowl, cream together the softened unsalted butter, brown sugar, and granulated sugar until light and fluffy, about 2-3 minutes.
Add the egg and vanilla extract to the butter mixture and beat until well combined. Gradually add the dry ingredients and mix gently until just combined.
Fold in the rolled oats and raisins until evenly distributed.
Scoop rounded balls of dough onto the prepared baking sheet, spacing them about 2 inches apart.
Bake for 10-12 minutes until the edges are lightly golden and the centers remain soft. Let cool on the baking sheet for 5 minutes before transferring to a wire rack.