3 egg whites
123gr granulated sugar
53gr cake flour
20gr cocoa powder
40gr powdered sugar
as preferred vanilla
180gr heavy cream, whipped to soft peaks
100gr white chocolate
60gr orange juice with or without liqueur
2,4gr gelatin sheets, softened in cold water
2Tbs mandarin or orange marmalade
1tsp orange zest
170gr heavy cream
For the citrus cream warm the orange juice until slightly hot but not boiling and stir in the softened gelatin. When it's completely dissolved reheat if necessary to slightly warm up the mixture and pure it over the chocolate. Stir until the chocolate is melted, using microwave if needed, and add the zest and marmalade. Set aside to cool until lukewarm and finally fold in the whipped cream. Keep in fridge until set and spreadable, even overnight.
Continue with the sponge cake by shifting the flour with cocoa powder and separately combining the eggs yolks, sugar and vanilla in the bowl of a mixer fitted with the whisk attachment. Whisk the mixture at high speed until thick ribbon stage and pale in color. In a separate bowl whisk the egg whites with powdered sugar to meringue Add the meringue to the yolk mixture alternately with the flour and fold as few times as possible and carefully not to deflate until combined. Spread the batter on a 30x40cm lined sheet pan and bake at a preheated convection oven to190C for about 12min until it has gained a slight color and springs back when touched.
Then let it cool, turn it upside down and remove the parchment paper from the bottom. Spread the cream on that surface after giving it a little stir to soften and roll the sponge cake lengthwise in an tight and even manner. Keep it in fridge rolled in the parchment paper and make the ganache by combining the chocolate with the heated until hot cream. Stir until completely smooth and finally pure over the sponge cake roll. Refrigerate for the cake to set and optionally serve with orange confit and and chocolate decorations.