Boil/microwave your potatoes until they are cooked thoroughly and break up the potatoes with a fork. Make sure you don't mash them up too much because we still want some chunks of potatoes in our mixture.
In a pan, heat up your oil on a medium heat and then add in your cumin seeds. Sauteé for about 20 - 30 seconds.
Add in your red onions, and sauté until they are translucent.
Add in the rest of your spices except for the salt,
Add in your potatoes and peas, and if needed, a few tbsp of water, to prevent the mixture from drying out.
Now add in your salt.
Cut up your puff pastry sheet into 6 evenly sized rectangular pieces and roll each piece into a cone. Seal the edge of your cone with some water and press firmly.
Fill your cone with the potato stuffing you just made, and then close off the bottom of the cone, once again using water to seal off the edges.
Pop your samosas into the oven for about 22 minutes.