Preheat the Oven:
Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper or a silicone baking mat.
Prepare the Dry Ingredients:
In a medium bowl, whisk together the rolled oats, flour, baking soda, salt, and ground cinnamon. Set aside.
Mix the Wet Ingredients:
In a large mixing bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy. Beat in the egg and vanilla extract until well combined.
Combine Wet and Dry Ingredients:
Gradually add the dry ingredients to the wet mixture, mixing until just combined. Be careful not to overmix. Gently fold in the diced strawberries and white chocolate chips (if using).
Scoop and Bake:
Using a spoon or cookie scoop, drop rounded tablespoons of dough onto the prepared baking sheet, spacing them about 2 inches apart. Flatten the cookies slightly with the back of the spoon.
Bake:
Bake in the preheated oven for 10-12 minutes, or until the edges are golden brown and the centers are set. Allow the cookies to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.