1. Preheat oven to 300 degrees.
2. Grease the bottom and sides of a 9″ x 9″ square pan with butter. Lay a piece of parchment paper across the bottom and up the sides of the pan, allowing the paper to hang over the sides of the pan by one to two inches. Butter the bottom and sides of the paper, and dust the bottom and all sides with cocoa. Set aside.
3. In the bowl of a stand mixer, fitted with the paddle attachment, mix the eggs on medium speed until they are light, foamy, and lemony.  Add the vanilla and mix to incorporate.
4. Place a wire mesh strainer or a sifter over the mixing bowl. Place the sugars, flour, salt, cayenne pepper, cinnamon and cocoa in the strainer, and sift the ingredients into the mixing bowl. Mix the ingredients on medium speed just until the dry ingredients are incorporated.
5. Slowly add the butter with the mixer on low speed. Mix only until the butter is mixed in and stop mixing.
6. Spread the batter into the prepared pan.
7. Bake for exactly 45 minutes. A toothpick inserted into the center of the brownies should come out clean. Place the brownies on a hot pad in the refrigerator to cool while you make the chocolate ganache.

Chocolate Ganache:

1. Pour the whipping cream in a small saucepan, and bring just to a boil over medium heat and remove. Pour the whipping cream over the chocolate pieces and set it aside for about 7 to 8 minutes, until the chocolate has time to soften. Mix the whipping cream and chocolate together, until they are well combined and the chocolate is melted. The mixture will be somewhat thin. Transfer about 1/3 of the ganache into a piping bag fitted with a small round tip.
2. Remove the brownies from the refrigerator. Spread the remaining ganache over the top of the brownies. Sprinkle the marshmallows over the ganache, pressing them lightly into the ganache.
3. Turn your oven to broil. Place the pan under the broiler, while watching closely, until the marshmallows are golden brown and remove. You can also use a kitchen hand torch for this. 
4. Place the brownies back in the refrigerator for a few minutes until the ganache has firmed up. Then pipe the remaining chocolate in the bag back and forth over the marshmallows. Place the pan back in the refrigerator long enough for the chocolate to set.
5. Grab the edges of the parchment paper and pull straight up as you lift the brownies, paper and all, out of the pan and place them on a countertop. Cut the brownies into nine large brownies, by using a pizza cutter or a long sharp knife.
6. Store brownies in an airtight container with wax paper between them for up to 3 days.