First, boil the espresso and let it cool. Finely grate the lemon zest and squeeze out one half. Mix the mascarpone with the milk, sugar and vanilla sugar until smooth, preferably with a hand mixer. Mix in the lemon zest and juice. Line the bottom of a tall rectangular mold with ladyfingers.
Mix espresso with grappa and spread a little on the cookies. Spread a third of the cream on the cookies, top with ladyfingers, soak them, spread cream again, top with cookies, soak them and finally cream again. Mix cocoa powder with cinnamon and drizzle on the tiramisu. Leave in the refrigerator for 8 hours.