Place your oats in a food processor and pulse about 5-10 seconds.  Set aside.

Beat butter in the bowl of a stand mixer (or using an electric beater) for about 30 seconds. Add sugars and beat until light and fluffy (pause to scrape down sides and bottom of bowl, if needed).

Add eggs, one at a time, beating until combined.

Stir in vanilla extract

In a separate bowl, whisk together flour, cornstarch, baking soda, salt, and cinnamon.

Gradually add flour mixture to butter mixture until completely combined. Be sure to scrape the sides and bottom of the bowl so ingredients are well-mixed.

Gradually stir in oats until completely combined. Add white chocolate chips and cranberries and stir well.

Chill dough in refrigerator for 30 minutes.

Preheat oven to 375F (190C) and prepare cookie sheets by lining with parchment paper.

Drop cookie by rounded 2 Tablespoon-sized ball onto parchment paper, spacing at least 2" apart.

Bake on 375F for 10-12 minutes or until edges are lightly golden brown (centers may still seem slightly underbaked, they'll finish cooking as they cool on the cookie sheet)

Allow cookies to cool completely on cookie sheet before serving and enjoying.