Recipe from Sue Phillips
2 1/2 cups all-purpose flour
1 1/2 cups sugar
2 teaspoons baking soda
2 tablespoons vinegar
2 cups cold coffee
Mix flour, 1 1/2 cups sugar, cocoa, baking soda, and salt in a large bowl. Mix wet ingredients and whisk together with the previously mixed dry ingredients. Pour the mixture into an ungreased 13"x9"x2" metal baking pan.
Next, mix the 1/4-cup sugar and the cinnamon and sprinkle evenly over the top of the batter.
Bake for 35-40 minutes or until a toothpick inserted comes out clean.
(The original directions call for mixing the dry ingredients: flour, 1 ½ cups sugar, cocoa, soda, and salt in the pan, making three wells, and pouring the oil in one well, vinegar in another, and vanilla in the last one; then, pouring the coffee over all of it and mixing with a fork. I find that it is easier to just mix it in a bowl and pour it into the pan.)