Prepare the sponge by beating eggs with sugar until pale and thick, then gently fold in sifted flour so the mixture keeps as much air.
Pour the batter into a lined baking tin, level the surface carefully, and bake at 180°C until golden, springy, and fully cooked through the center.
Remove the cake from the oven, cool it completely, then slice it horizontally into layers using a long serrated knife for clean, even sections carefully.
Mix strong cooled coffee with sugar, then brush each cake layer generously so the sponge absorbs moisture and develops a deep coffee aroma throughout evenly.
Whip the cold cream with powdered sugar and vanilla until firm peaks form, taking care not to overbeat because the cream can quickly become grainy.
Spread whipped cream between the coffee-soaked cake layers, stacking them neatly, then cover the top and sides with the remaining cream in an even layer.
Press chopped toasted nuts over the top and sides, adding extra coffee powder or cocoa if desired for stronger color, aroma, and decorative contrast overall.
Refrigerate the assembled cake for at least three hours before slicing, allowing the layers to settle and the coffee, cream, and nuts to harmonize fully.
