Preheat your oven to 200°C (400°F) and line two baking trays with baking paper.
Peel and dice the onion and carrot. Chop the potatoes into 1cm cubes and set aside.
Heat the oil in a frying pan with high sides or a small dutch oven over medium-high heat. Add the onion and carrot and sauté for 5 minutes, or until the onion is soft. Turn down the heat if they are browning too quickly.
Add the potatoes, curry powder, turmeric and salt and stir until everything is well coated in the spices. Cook for a further minute or two until the spices are fragrant.
Pour in the vegetable stock, scraping the bottom of the pan with a wooden spoon.
Reduce the heat, place the lid on and cook for 10–15 minutes, or until the potatoes are cooked through. Check frequently and scrape the bottom of the pan to prevent sticking. add a little more stock if needed. Once cooked, mix through the frozen peas, then set aside to cool completely.
While the filling cools, remove the puff pastry sheets from the freezer and allow to defrost on the bench.
Cut each sheet of pastry into 9 squares and place a heaped tablespoon of filling into the centre of each. Fold in half and crimp the edges firmly to seal. Brush the tops with a little dairy free milk or beaten egg. Sprinkle over sesame seeds if using. Place evenly spaced on the prepared trays.
Bake for 25 minutes, or until the tops are golden brown. Serve warm.