01 - Toss peach slices with lemon juice and sugar in a bowl. Set aside for 10 minutes to macerate and release natural juices.
02 - In a large mixing bowl, whip cold heavy cream using a hand mixer or stand mixer until soft peaks form.
03 - Combine mascarpone cheese, sugar, and vanilla extract in another bowl. Mix until completely smooth and creamy.
04 - Gently fold whipped cream into mascarpone mixture until fully incorporated and smooth.
05 - Combine peach juice and schnapps (if using) in a shallow dish.
06 - Quickly dip each ladyfinger into peach juice mixture, ensuring moistening without soaking through.
07 - Arrange half soaked ladyfingers in single layer at bottom of 9x7 inch serving dish. Spread half mascarpone cream evenly over ladyfingers, then top with half sliced peaches.
08 - Repeat with remaining soaked ladyfingers, mascarpone cream, and peach slices to complete second layer.
09 - Cover dish and refrigerate for at least 4 hours or overnight to allow flavors to meld and texture to set.
10 - Remove from refrigerator and garnish with fresh mint leaves immediately before serving.