Halve or quarter the potato. Boil the potato in a pan of boiling water until soft and mashable. Around 15-20 minutes depending on the size. Drain and set aside to cool.
Heat the oil in a medium frying pan on a medium heat. Fry the onion until soft, around 5 minutes.
Add the ginger, garlic and fresh chilli (if using) into the pan and fry for a further minute.
Combine the dried spices in a small bowl with 1 tbsp of water then add to the frying pan. Cook for 3 more minutes.
Cut the potato into 1cm cubes and add to the pan with a pinch of salt. Stir and squash the potatoes. Cook for 5 minutes continuing to squash the potatoes.
Add in the frozen peas and cook for around 3 minutes until the peas are cooked through. The mixture should be dry but add a splash of water if it is sticking to the pan.
Take off the heat and stir in the coriander.
Leave the potato mixture to cool completely.
Preheat the oven to 220°C/200°C fan (425°F/400°F).
Lightly flour a work surface, lay out the pastry and, using a 9cm/3.5inch circular cutter, cut out discs of pastry. Re-roll the leftover dough to cut as many discs as you can.
Place the discs on baking trays lined with baking paper. Use the egg wash to brush one half of each pastry dish. Take a disc in your hand, place a tablespoon of mixture in the centre, fold over and crimp the edges with your fingers.
Once all of the pastries have been assembled, evenly space them on the baking tray and brush all over with egg wash.
Bake in the oven for 16-20 minutes until golden all over. These are best served warm!
