01 -
Heat the oven to 190°C (375°F), conventional heat. Line the base of 30 × 40 cm shallow baking tray with baking parchment and lightly grease the sides.
02 -
Beat eggs and sugar with an electric mixer for 7–9 minutes until pale, thick and ribboning. Sift the flour over in two portions and fold carefully. Mix oil and milk with two spoonfuls of batter in a small bowl, then gently fold this mixture back in. Spread evenly in the lined tray.
03 -
Bake at 190°C for 10–13 minutes until the surface springs back and no wet batter remains. While warm, invert onto a fresh sheet of baking parchment, peel away the baking paper and roll from the short edge with the fresh paper inside. Cool rolled for 30–45 minutes.
04 -
Measure the flavor ingredients separately. Chop nuts and dried fruit into small pieces. Dice apple or pear to 5 mm. Wash citrus before grating only the colored zest. Dissolve any instant coffee in 10 ml hot water and let it cool.
05 -
If apple or pear is included, cook the small diced pieces with 10 ml water in a small covered saucepan for 5–8 minutes until tender. Uncover and evaporate any free liquid, then cool completely. Do not add warm or watery fruit to cream.
06 -
Briefly stir the cold mascarpone with powdered sugar until smooth. In a separate cold bowl whip the cream to firm peaks, stopping before it becomes grainy. Fold the whipped cream into the mascarpone in two additions with a spatula.
07 -
Fold all the prepared flavor ingredients into the cream, including any cooled coffee or cooked fruit. Chop chocolate finely; do not melt it into the cream. Keep the cream cold while assembling.
08 -
Carefully unroll the completely cool sponge and remove the paper. Spread the flavored cream evenly, leaving 2 cm clear at the far short edge. Roll up gently without paper and place seam-side down. Cover and chill at least 2 hours before cutting. Small surface cracks are normal; do not force a cold, stiff sponge flat.