Preheat oven to 325 degrees. Lightly coat a 9x13 inch baking pan with cooking spray. Set aside.
In a large saucepan melt the butter over medium heat. Whisk in the cocoa and espresso powder, followed by the water and sugar. Whisk after each addition until very smooth. Remove pan from the heat and set aside to cool.
In a medium bowl, combine flour, cinnamon, baking soda, salt, cayenne pepper, chili powder and chocolate chips. Mix well and set aside.
To the butter/chocolate mixture add 2 large eggs, vanilla and whisk until fully incorporated. Gently stir in the flour mixture and using a rubber spatula pour the cake batter in the prepared pan.
Bake for 35 to 40 minutes until a toothpick inserted into the center comes out clean. Remove from the oven and cool completely before frosting.