Cherry Puff Pastry Tarts

1  1/2 cups pitted cherries

1 tbsp white sugar

1  1/2 tsp cornstarch

1 tsp lemon juice

1/2 package puff pastry (~198.5g / 7oz), thawed

(optional) 1 egg, separated

(optional) ~ 1/2 tsp x4 white sugar

1. Remove puff pastry from freeze to thaw
2. Stir together pitted cherries, white sugar, corn starch and lemon juice together until cherries are evenly coated.
3. Roll out puff pastry, cut into 4 squares, place onto cookie sheet lined with parchment paper.
4. Spoon cherry mixture onto puff pastry.
5. Fold up edges of pastry and pinch together (optional tip: use egg yolk to help stick edges together)
6. (optional) Brush edges with egg white and sprinkle whole pastry with 1/2 tsp white sugar.
7. Bake at 350F for 25-35 minutes until pastry is golden brown