In a medium-sized saucepan on medium heat, stir 1 cup peaches, 1 cup mangoes, 2 tbsp peach syrup (from the can), 2 tbsp brown sugar, ¼ tsp cinnamon and a pinch of salt. Taste and see if you're okay with the level of sweetness. If not, adjust and add more syrup and/or sugar.
Cook until the fruits start breaking down and the mixture starts to reduce and thicken (about 20 minutes). I like to help it along by squishing the fruit as I’m stirring. Stir often.
Once thick enough, add 1 tbsp cornstarch dissolved in 1 tbsp water, stir to combine, and continue to cook until you get a significantly thicker consistency. This usually only takes a couple of minutes.
Add ½ tsp vanilla, stir to combine and remove from heat. Set aside to cool.
Assembling your peach pies
Line a baking pan or cookie sheet with parchment paper and set aside.
In a small bowl, prepare your egg wash by beating a large egg with 2 tbsp milk. Set aside.
Gently roll out your thawed puff pastry sheets onto a lightly floured surface. Use a rolling pin to seal the perforations and shape the puff pastry into a circle.
Lay a drinking glass or a cookie cutter on the dough, press firmly straight down and lift straight back up.
Take your puff pastry pieces and place them on your baking sheet. Space them out evenly.
Scoop 1-2 tbsp of filling in the middle then place another piece of puff pastry on top.
Crimp and seal the edges with a fork.
Using a small, sharp knife, make 2 small cuts on top of the pies so that air can escape while baking.
Brush the pies with egg wash and, optionally, sprinkle with demerara or brown sugar.
Place the pies in the freezer while you pre-heat the oven to 375F.
When ready, bake for 20 minutes or until golden brown. Rotate the pan midway during baking. Enjoy!
The number of pies/yield depends on how you cut your puff pastry. If circles like in the photos, I can make 10 pies using a glass/cookie cutter that's roughly 3 inches in diameter. If you choose simple rectangles like in this ube pie recipe, you'll have enough for 6 fairly large pies.
If you want to use fresh fruit, you can replace the canned peaches with 2-3 ripe peaches (250g once peeled, pitted, diced) and 1-2 ripe mangoes (150g once flesh scooped out and diced). Adjust the sugar content depending on how sweet your fruits are. Then cook the same way.