Preheat oven to 350F. Grease the bottom and sides of a 16x11 inches swiss roll pan with melted or softened butter. Line the base with parchment paper
Beat eggs and sugar on high using mixer until very light and fluffy. It should hold it's shape for a few seconds -ribbon stage
Meanwhile, combine flour, cocoa powder, coffee, baking powder and salt in a separate bowl, stir well to combine and sift. Set aside.
Mix the combined dry ingredients with the beaten egg by folding. When done, pour batter into the prepared baking pan.
Bake for 10 minutees or until the surface springs back when lightly tapped
While cke is baking, place a sheet of parchment paper (same size as the baking pan) on a clean surface, dust with cocoa powder
When cake is done, turn it immediately onto the cocoa-dusted parchment paper. Remove the paper on top of the cake, carefully roll the cake starting at the end near you; place seam-side down on a wire rack to cool.