Preheat your oven to 400°.
Cover your pie dish or springform pan with parchment paper.
Lay your defrosted puff pastry sheet on top of parchment paper and poke a few holes with your fork.
In a bowl, combine the sliced peaches and blueberries with lemon juice, cornstarch and sugar mixed together, and pour into your puff pastry sheet.
Add some lemon zest for brightness.
Fold over edges of puff pastry sheet and brush with egg wash around crust and sprinkle sugar on crust.
Pop into oven for about 35 minutes or until golden brown crust.
Serve with ice cream or whipped cream or powdered sugar on top.
