Mix the blueberries, sugar and lemon juice in a pan, bring to the boil. Simmer the mixture for approx. 5 mins., transfer to a bowl, leave to cool.
Bring the lemon zest, lemon juice and sugar to the boil in a pan, simmer until the sugar has dissolved. Stir in the lemon liqueur, leave to cool.
Lemon mascarpone cream
Combine the mascarpone, sugar and lemon liqueur, fold in the whipped cream.
Dip the sponge fingers in the syrup, layer in the glasses along with the mascarpone cream, coulis and berries, garnish with mint.