Preheat oven to 350F
In a medium bowl, combine all dry ingredients - flour, oats, baking powder, baking soda, salt, and cinnamon. Set aside
In a large bowl, add the butter and brown sugar. Cream, using a hand mixer (or do this all in the bowl of a stand mixer fitted with a paddle attachment) until light and fluffy, about 5 minutes
Scrape the sides of the bowl with a nonstick spatula. Then add in the two egg yolks and vanilla. Mix again until smooth and scrape the sides of the bowl again
Add in dry ingredients and mix until thick dough forms. Add in cranberries and chocolate and mix until evenly distributed
Line a large cookie sheet with parchment paper and scoop dough into 2 tablespoon-sized balls. Place the cookie dough balls no less than 2.5 inches apart. Bake for 11-15 minutes or until the cookies have set slightly browned edges
Remove from the oven and let cool for at least 10 minutes before enjoying!