Preheat the oven to 350 degrees. Line two baking sheets with parchment paper.
In a medium bowl, whisk together the flour, cocoa powder, baking powder and salt. Then set aside the flour mixture.
1 ½ cups (188 g) all-purpose flour, spooned and leveled , ½ cup (40 g) Dutch process cocoa powder, ½ teaspoon baking powder, ½ teaspoon salt
In a large bowl cream the softened butter, brown sugar and granulated white sugar together with an electric hand mixer on high speed until fluffy, about 2 minutes. (You can also use a stand mixer with a paddle attachment.)
¾ cup (168 g) unsalted butter, softened, ¾ cup (165 g) light brown sugar, packed, ¼ cup (50 g) granulated white sugar
Add in the egg yolks and vanilla and mix for one minute on medium speed until pale and fluffy.
2 egg yolks, at room temperature, 1 ½ teaspoon vanilla
Add in the dry ingredients and combine on low speed.
Scoop the dough into 16 portions with a 2 tablespoon cookie scoop, then roll into balls. Slightly flatten out each, then place a frozen cheesecake ball in the center. Then close the cheesecake ball in with the cookie dough and roll into a ball again. Make sure the cheesecake is completely covered in cookie dough. Roll the cookie dough balls in sugar.
¼ cup (50 g) granulated white sugar (for rolling the dough in)
Transfer the cookie dough to a prepared baking sheet lined with parchment paper. Bake 6 cookies at a time for 10-11 minutes.
Let the cookies cool for 10 minutes on the cookie sheet, then place cookies on a wire rack to cool completely. Then serve!