Instructions

1. In a small saucepan over medium heat, melt ¼ cup (60 ml) sugar in ¼ cup (60 ml) water. Add ginger and bring to a boil. Reduce heat and simmer for 5 minutes. Turn off heat, cover and allow syrup to steep as it cools. When completely cool, mix in ginger liqueur, if using. Can be prepared 1 day ahead and refrigerated until ready to use. Remove ginger slices before using, or for added ginger flavour, finely chop strained ginger and reserve for step 11.
2. Preheat oven to 350 F (180 C). Grease and line a 10 x 15-in (25 x 38 cm) jelly roll pan with parchment paper. Place a clean tea towel on counter and evenly dust 1 tbsp (15 ml) icing sugar over it. Set aside.
3. In a medium bowl, whisk together egg whites, cream of tartar and salt until frothy. Gradually add ¼ cup (60 ml) sugar and whisk until soft peaks form. Set aside.
4. In a large bowl, whisk together egg yolks and remaining ¼ cup (60 ml) sugar until thick, pale and fluffy (this is called ribbon stage: when whisk is lifted from batter, it should fall in shape of thick ribbon). Whisk in oil, milk and vanilla until well incorporated.
5. Sift ¼ cup (60 ml) flour over whipped egg yolk mixture and gently fold in, then fold in ⅓ of the whipped egg whites. Do not over mix. Fold in remaining whipped egg whites until no white streaks remain. Sift over remaining ¼ cup (60 ml) flour and fold in.
6. Pour batter into prepared pan and evenly smooth surface with an offset spatula. Bake for 12 to 15 minutes, or until surface springs back up when lightly pressed.
7. Remove cake from oven and immediately invert onto prepared tea towel. Gently peel off parchment paper and evenly dust 1 tbsp (15 ml) icing sugar over surface of cake. Starting from long edge of cake, fold tea towel along with cake into a roll. Set aside to cool.
8. In a heatproof bowl set over a small saucepan with simmering water, melt white chocolate, stirring constantly. Do not allow water to touch bottom of bowl. Once melted, remove from heat and whisk well until smooth. Let cool slightly.
9. In a medium bowl, whisk cream cheese until no lumps remain. Pour melted chocolate over and mix until fully incorporated. Set aside to cool.
10. In another medium bowl, whip cream until soft peaks hold their shape. Fold ⅓ of whipped cream into cream cheese mixture until no white streaks remain. Fold in remaining whipped cream until incorporated. Do not over beat.
11. On a clean, dry surface, unroll cake and remove tea towel. Using a pastry brush, evenly brush ginger syrup over surface of cake. Using an offset spatula, spread white chocolate filling over cake in a ½-in (1.25 cm) layer. Reserve and refrigerate any remaining filling. Evenly scatter reserved chopped ginger over filling, if desired. Roll cake back into a log, scraping off any excess filling from edges. Wrap cake in parchment paper and refrigerate for at least 4 hours and up to 24 hours.
12. To serve, trim off cake ends. Sprinkle remaining 1 tbsp (15 ml) icing sugar over surface of cake and decorate with reserved white chocolate filling and any other decorations, as desired.