Method

• 1.
  Place 1 cup (250ml) espresso and 150g caster sugar in a small saucepan over low heat, stirring to dissolve sugar. Remove from heat. Add 1 cup (250ml) chilled espresso to the syrup. Set aside.

• 2.
  Place eggs and 150g sugar in a heatproof stand mixer bowl set over a saucepan of gently simmering water (do not let the bowl touch the water). Using a whisk, stir for 6-8 minutes until sugar has dissolved and mixture reaches 60°C on a kitchen thermometer. Transfer to a stand mixer with the whisk attachment and whisk until completely cooled, pale and fluffy. Whisk in cream and vanilla on high speed until stiff peaks form (about 5 minutes). Turn off mixer. Add mascarpone and 1/2 cup (125ml) coffee syrup. Whisk on low speed until combined and thick.
• 3.
  Add vodka and coffee liqueur to remaining coffee syrup. Dip one-third of the savoiardi biscuits into the syrup and use to line the base of a 32cm-wide 6cm-deep serving dish. Spread one-quarter cream mixture over the top. Repeat layering with remaining biscuits, coffee syrup and one-quarter cream mixture, to create 2 more layers, finishing with remaining cream mixture. Use a palette knife to create peaks. Chill overnight until firm and set.
• 4.
  Place remaining 100ml coffee and remaining 1 cup (220g) sugar in a saucepan. Place over medium heat, stirring to dissolve sugar. Bring to a simmer and reduce to low. Cook, stirring constantly, for 6-8 minutes until thickened. Transfer to a bowl and cool, stirring occasionally so it doesn’t set. Pour cooled syrup over tiramisu and dust with cocoa to serve.