"Simple brownies made with Mexican hot chocolate disks. Great way to use them up! Enjoy! This recipe was borne from a desire to use up Mexican hot chocolate discs, which have a lot of sugar and some oil already. I used Ibarra® brand and the brownies were fantastic with a mild cinnamon flavor. I wouldn't try to substitute this ingredient."
Preheat oven to 350 degrees F (175 degrees C). Line an 8-inch baking pan with parchment paper.
Combine instant coffee and boiling water in a bowl.
Melt chocolate tablets and butter in the top of a double boiler set over a pot of simmering water, about 5 minutes. Add coffee, vanilla extract, cinnamon, and salt. Mix the chocolate mixture and flour together in a second bowl.
Beat eggs together in another bowl. Combine eggs and chocolate-flour mixture. Pour into the prepared baking pan.
Bake in the preheated oven until set and surface is glossy, about 20 minutes.