Heat 1 tbsp of oil over medium heat.
Add the onions, garlic, and potatoes. Cook for 2-3 minutes until the potatoes are almost cooked through.
Add the ground chicken and cook for 1-2 minutes until the chicken is cooked through.
Next, add the frozen vegetables, curry powder, salt, sugar, fish sauce, and coconut cream. Stir and cook for 5 minutes until the sauce thickens. Set the filling aside to cool for 20 minutes.
Preheat the oven to 400 degrees F (204 degrees C).
Defrost the puff pastry sheets and roll them out.
Use a 3½ inch biscuit cutter to cut the puff pastry into even circles. Add 1-2 tbsp of filling to a pastry cut out. Cover with another pastry cut out. Use a fork to press the edges of the pastry closed. Score the top of the pastry with a knife. Repeat this process until you run out of pastry sheets or filling. If you have leftover pieces of dough, combine them and roll it out to make more pastry cut outs.
Prepare 2 baking sheets by covering them with parchment paper. Place the pastries on the baking sheets and put them in the fridge to cool for 5 minutes.
Whisk an egg. Use a pastry brush to brush egg wash on the tops of the pastries.
Bake for 20-22 minutes until golden brown.
Cool for 5 minutes before serving.