Preheat the oven to 180°C.
Heat the apple juice and honey together in a small saucepan over low heat, until the honey melts. Set aside.
To make the filing, combine the biscuits, walnuts, ground almonds, sugar, butter, lemon zest and cinnamon together in a small bowl.
Core the apples and score the skin around the circumference, so that it splits nestly during cooking. Stuff the apples with amaretti filling and arrange upright in a small baking dish.
Pour the syrup around the apples and bake, uncovered, for 35-45 minutes until tender. Serve drizzled with syrup, or mascarpone if desired.
