Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper if desired.
In a medium bowl, cream together the softened butter, brown sugar, and white sugar until light and fluffy.
Beat in the egg and vanilla extract until well combined.
In another bowl, whisk together the rolled oats, flour, baking soda, salt, and cinnamon.
Gradually add the dry ingredients to the wet mixture, stirring until just combined.
Fold in the dried cranberries evenly into the cookie dough.
Using a tablespoon or cookie scoop, drop dough onto the prepared baking sheet, spacing them about 2 inches apart.
Bake in the preheated oven for 10-12 minutes or until the edges are golden brown.
Remove the cookies from the oven and allow them to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.