Step 1

Preheat the oven to 350°F (180°C).

Step 2

Butter or spray an 8x11-inch baking pan.

Step 3

Line it with a piece of parchment paper if you want, covering the bottom of the pan and two long sides. The two short sides will remain unlined but greased. This will help you remove the cake from the pan.

Step 4

Combine sifted flour mixture (1 ¾ cups self-rising flour, ¼ teaspoon salt, and 1 teaspoon baking soda) with sifted ¾ cup cocoa powder, 1 cup sugar, 1 cup brown sugar,1 ½ teaspoons ground cinnamon, and ⅛ to ¼ teaspoon ground cayenne (depending how spicy you want it) in a large mixing bowl.

Step 5

Add 2 eggs, ½ cup vegetable oil, 1 cup milk, and 1 ½ teaspoons vanilla extract and beat at medium speed for 2 minutes, until smooth and no lumps remain.

Step 6

Heat 1 cup prepared coffee (or water) until it's about to boil and add to the chocolate batter in a thin stream, beating at low speed until completely incorporated and smooth.

Step 7

Pour thin batter into the prepared pan. It will be very thin.

Step 8

Bake for about 40 minutes, until the top springs and a cake tester or toothpick inserted in the center comes out clean.

Step 9

Let cake cool completely on a wire rack. Make sure the sides of the cake are not stuck to the pan and remove it carefully, helping lift it with the parchment paper.

Step 10

Transfer to the serving plate after removing the paper.

Step 11

Spread cinnamon frosting on top (I use an offset spatula or the back of a spoon) and sprinkle with chopped chocolate (or mini chocolate chips)and ground cinnamon if you want to.

Step 12

Cut into squares and serve.

Step 13

Store leftovers in the refrigerator, well covered.

Step 14

Beat ½ cup cream cheese in a medium bowl with the softened ¼ cup unsalted butter until very creamy and no lumps remain.

Step 15

Gradually add 2 cups powdered sugar and beat until you have a thick, very creamy consistency, good enough to spread.

Step 16

Add 1 teaspoon ground cinnamon, ½ teaspoon vanilla extract, and Pinch salt. Beat again until completely incorporated and smooth.

Step 17

It keeps well in the refrigerator for a few weeks. Beat again before using to attain a creamy consistency.