Preheat the oven to 350 degrees Fahrenheit. Grease and flour a 9-inch round cake pan.
In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time.
In a separate bowl, sift together the flour, cocoa powder, baking powder, baking soda, and salt. Slowly add the dry ingredients to the creamed mixture, alternating with the buttermilk and coffee.
Stir in the Serrano peppers and chocolate chips. Pour the batter into the prepared pan.
Bake for 40-45 minutes, or until a toothpick comes out clean. Allow the cake to cool in the pan for 10 minutes before turning out onto a wire rack.
Serve warm with a dollop of whipped cream.
Interesting Facts
Serrano peppers are a type of chili pepper that originate from Mexico.
This cake is not overly spicy, but it does have a subtle heat to it.
This cake is best served warm with a dollop of freshly whipped cream.