15mint oreos -- broken into pieces(I place mine in a large Ziploc bag and bang with a rolling pin until they are broken into pieces no larger than a nickel)
1/2cupmini chocolate chipsoptional
Combine butter and chopped semisweet chocolate in a large microwave-safe bowl and microwave for 30 seconds. Stir well, return to microwave and heat again for 15 seconds. Repeat microwaving and stirring until chocolate is completely melted.
Allow chocolate mixture to cool for at least 10 minutes before continuing.
Once chocolate is no longer very hot, stir in brown sugar.
Add eggs and egg yolks, one at a time, stirring very well after each addition.
Stir in vanilla extract. Set aside.
In a separate, medium-sized bowl, whisk together flour, baking powder, salt, and baking soda.
Gradually stir flour mixture into chocolate mixture until completely combined.
Stir in Oreo pieces and mini chocolate chips (if using). Cover loosely with clear wrap and chill in refrigerator 2 hours.
Preheat oven to 350F and line a cookie sheet with parchment paper.
Once dough has finished chilling, scoop into 1 1/2 Tablespoon-sized balls and drop on prepared baking sheet.
Bake on 350F for 12 minutes (centers will still be slightly soft). Allow cookies to cool on baking pan for 5 minutes before transferring to cookie sheet to cool completely.