Preheat your oven to 350°F (175°C). Grease your baking pan or line it with parchment paper for easy removal later.
In a medium saucepan over low heat, melt the unsalted butter along with the semisweet baking chocolate, stirring constantly until fully melted and smooth. Remove from heat and let cool slightly.
In a large mixing bowl, whisk together the eggs and sugar until the mixture is light and fluffy.
Stir in the vanilla extract and the melted chocolate mixture into the egg and sugar mixture. Mix until well combined.
In a separate bowl, whisk together the all-purpose flour, instant coffee granules, salt, ground cinnamon, and cayenne pepper.
Gradually fold the dry ingredients into the wet mixture until just combined. Be careful not to overmix.
Gently fold in the dark chocolate chips for extra chocolatey goodness.
Pour the brownie batter into the prepared baking pan, spreading it evenly. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.
Once baked, remove the brownies from the oven and let them cool in the pan for about 15 minutes. Then, lift them out using the parchment paper and let them cool completely on a wire rack. Dust the top with powdered sugar and a sprinkle of cayenne pepper before serving.
