Preheat the oven to 350 degrees and line a large baking sheet with parchment paper.
In a stand mixer with the beater blade attachment (or just a hand mixer), beat the butter, granulated sugar, brown sugar, melted chocolate, and vanilla until smooth. Add the eggs and mix until combined.
In a separate bowl, add the flour, cocoa powder, baking powder and use a fork to mix together. Slowly add the flour mixture to the wet mixture and mix until combined. Add the vanilla and fold in the chocolate chips. The dough will be wet.
Use a cookie scooper to place dough, about 1½ tablespoon balls onto the prepared baking sheet, about 2 inches apart. Bake for 9-11 minutes or until cookies are not glossy anymore. Do not overbake! The difference between an amazing cookie and a mediocre one is if it is baked correctly. I like to press extra chocolate chips on top of the cookie right after they come out and sprinkle with a little flaked salt. Let cookies cool on the baking sheet, then transfer to a cooling rack.
Notes
FREEZING COOKIES
Scoop cookie dough balls onto a baking sheet and freeze for at least 30 minutes. Then you can transfer the balls to a freezer bag and freeze up to 3 months. To bake: bake as directed from frozen adding 2-3 minutes to the bake time or just until cookies aren't shiny but are set. Source: Trisha Yearwood