Using a double broiler, melt the butter and bittersweet chocolate; stirring constantly until smooth. Remove from heat.
In a stand mixer (using a paddle attachment), beat the eggs, sugar and vanilla extract until thick and smooth.
Add the melted butter and chocolate mixture to the stand mixer and beat on low-medium speed until combined.
In a mixing bowl, whisk together the flour, salt, baking powder, cinnamon and cayenne pepper.
Slowly add the dry ingredients to the stand mixer 1/2 cup at a time to avoid a flour bomb in your face.
Stir in the semisweet chocolate chips until combined.
Refigerate the dough for at least 30 minutes (this will prevent the cookies from spreading out too far when baking).
Preheat oven to 350°F and scoop the dough (using a cookie scop) about 2" to 3" apart on a parchment lined baking sheet. Bake for 10 minutes.
Remove the baking sheet from the oven and place 3 to 4 bitterweet chocolate chips on top of each cookie. Let the cookies rest at least 5 minutes before transferring to a cooling rack.
Cool completely; store in an airtight container.