Preheat oven to 350°. Grease three 9-inch round cake pans. Cover each bottom with disc of parchment paper. Grease and flour again. In large separate bowl, mix together flour, sugar, cocoa, salt and baking soda. Gradually add wet ingredients to dry until well mixed. Gradually add hot coffee. Scrape batter into prepared pans. Bake cake for 25 to 30 minutes or until toothpick inserted in center comes out clean. Let cakes rest in pans for 10 minutes and then turn on to wire rack to cool completely.
Mix sugar and milk in saucepan. Add butter. Bring to a boil. Remove from heat. Add chocolate chips to pan. Using wire whisk, mix until smooth. (Note: if frosting is too thick or grainy, add 1 to 2 teaspoons hot coffee).
Place 1 cooled cake layer, top side down, on cake plate. Spread 1/3 of frosting, pushing it out slightly from edges to make ripple pattern or petal effect on sides. Refrigerate until ready to serve.