1 teaspoon lemon juice 500 g fresh strawberries, chopped small (1.1lb) 1 ½ tablespoons caster sugar (superfine sugar) 300 ml thickened cream (heavy / whipping cream), cold (1 ¼ cups) ⅓ cup caster sugar (superfine sugar) 500 g mascarpone, cold 2 teaspoons vanilla extract 28 Savoiardi/ladyfinger biscuits ½ cup Frangelico (hazelnut liqueur) 1 tablespoon freeze dried strawberry powder, optional