Dissolve espresso in 1/8 l boiling water. Add 1 tbsp. sugar and liqueur, let cool down.
Drain the cherries. Mix mascarpone, quark, lemon peel and 4 tablespoons of sugar.
Line the bottom of a rectangular form (approx. 15x15 cm) with half of the cantuccini. Drizzle half of the espresso over it and spread half of the mascarpone cream on top.
Spread the cherries, except for a few for decoration, on the cream. Place the rest of the cantuccini on top and sprinkle with the rest of the espresso. Spread the rest of the cream on top. Chill for about 3 hours.
Dust tiramisu thickly with cocoa. Decorate with remaining cherries and chocolate shavings.