Position 2 racks in the upper and lower thirds of the oven and preheat to 350º. Line two baking sheets with parchment paper.
In a medium bowl, sift together the flour, cocoa, cinnamon, chile, baking powder and salt. In the bowl of a stand mixer fitted with the paddle attachment (or the old-school way, with a bowl, wooden spoon and your supreme might) cream together the butter and sugar until lightened in color, 3 minutes. Add the eggs one at a time, then the vanilla. (It's not the end of the world if the mixture breaks.) Stir in the melted chocolate until combined, scraping down the sides of the bowl and the paddle as needed, then stir in the dries on low until just combined. Stir in the chopped chocolate and cacao nibs.
Remove the bowl and paddle, and use a sturdy rubber spatula to give the dough a final fold by hand
Scoop the dough into heaping-tablespoon-sized balls (I like to use the purple-handled spring-loaded ice cream scoop) and place 2 inches apart on the parchmented sheets. Bake 12 - 15 minutes, rotating top to bottom and front to back halfway through, until the centers are puffed, cracked and soft, and the edges are set. (Don't overbake.) Let cool completely on the sheets.
The cookies are best within the first couple of days after baking, but will keep in an airtight container for up to a week.
Adapted from Martha.I make these with chocolate that contains 70% cocoa solids. If using a chocolate with 60% solids or less (or one that doesn't say) increase the flour to 1 cup (5 ounces).My cayenne is on the elderly side (not sure how long it's been hanging around the spice cupboard) and the amount used here lends a warmth in the aftertaste, but not a tongue-scorching heat. (In fact, an unsuspecting five-year-old ate one at a party, and purportedly begged for another.) If your cayenne seems quite piquant, you might try decreasing the amount you use in the cookies.If you like, you can press a chocolate chunk or two and/or some extra nibs into the tops of the unbaked cookies. I couldn't decide which I liked better, aesthetically.Nutritional values are based on one of twenty four cookies.