Preheat oven to 350°. Line two cookie sheets with parchment paper and set aside.
If not using chocolate chips alone, chop up all of your chocolate, except the chips. Set all the chocolate aside.
In a medium bowl, whisk together 1 ½ cups of all-purpose flour, 1 ½ cups of cake flour, and 1 teaspoon of baking soda, and ½ teaspoon baking powder. Set aside.
In the bowl of your stand mixer combine ⅔ cup brown sugar, ⅔ cup granulated sugar, ¼ cup of turbinado(raw) sugar (if using), your brown butter, ½ cup (one stick or 113 grams) softened butter, ¾ teaspoon kosher salt, and 2 teaspoons vanilla bean paste or extract.
Beat until smooth and fluffy, 3-5 minutes. Scrape down the sides of the bowl to make sure everything is incorporated.
Add the eggs, one at a time, mixing in completely before adding the second egg. Scrape down the bowl afterward.
Add the flour mixture to the stand mixer one large spoonful at a time to avoid flinging flour all over the place. Don’t overmix, just a couple turns of the beater per-spoonful should do it.
Remove the bowl from your stand mixer and, using a rubber spatula (I actually like to use a rice paddle because it’s stiffer and has a short handle), make sure all the flour from the bottom of the bowl is incorporated. Add in your chocolate bits of choice and mix in by hand. If you want to add chocolate pieces to the top of each ball, set some aside before adding to the dough.
Using a 2 tablespoon scoop, scoop dough, shape into balls, then place on parchment lined sheet pan. If desired, press each ball a bit flat, add extra chocolate to the top, and form back into a ball with your hands.
Bake at 350° for 11-13 minutes. As soon as they come out of the oven, sprinkle with a little flaky sea salt, if you desire.
Let sit on the sheet pan for 5 minutes, then transfer to a cooling rack and finish baking the rest of the cookies before you eat them.