Preheat the oven at 200 C for 10 mins, before baking.
Shred the cooked beef / chicken in a food processor or using hands. Keep it aside.
Heat oil in a wide pan. Add chopped onion and cook till it becomes soft, no need to brown.
Add crushed ginger & garlic, chopped green chilli and curry leaves. Cook for 2-3 mins.
Add chicken / meat masala. Fry for 2 mins.
Add the cooked and shredded meat and mix well. Add 1-2 tbsp water or stock to bring it together.
Mix 1/2 - 1 tbsp Ketchup with 1/2 - 1 tbsp water. Add it to the meat mixture and stir well.
Thaw the puff pastry as per the package instructions. Beat 1 egg with 1-2 tsp water for egg wash. Apply this egg mixture on four sides of the puff pastry. Place about 1 -2 tbsp of masala on each puff pastry.
Close the puff pastry, by folding the two opposite corners of the square, to make a triangle. (refer notes) Apply the egg wash all over the sealed puffs. Bake in the preheated oven for 20-25 mins or until the puff pastry is golden in colour. Serve with tomato ketchup.
Notes
I used beef here and I pressure cooked the beef with salt and pepper. If you are using chicken, boil it with salt and pepper.I used store bought Puff pastry, however, I've given the link for homemade puff pastry.If you dont have chicken / meat masala, use 1/2 tsp garam masala and 1/4 tsp fennel powder. You can make the puffs in any shape you like. Also if you are using a big puff pastry sheet, then cut out single squares and use accordingly.If you want a rich/ dark brown color, change the oven setting to broiler (top portion baking) and bake for the last 2-3 mins.