Vegetable Samosas

Meg's Delicious and Easy Vegetable Samosas (makes 12-14 samosas)
For the filling:
10 small potatoes
2/3 cup peas (I used frozen ones)
1 onion
1 tsp cumin seeds
1/2 tsp mustard seeds
5 cardamom pods
1 inch cube of ginger, finely chopped
2 small cloves of garlic
1 tsp sweet paprika
1/2 cup chopped mint
1-2 chopped hot green peppers, depending on how spicy you like your samosas
juice of half a lime
salt
a little vegetable oil
For the pastry:
1 1/2 cups flour
1 container of plain yogurt (about 6 Tbs)
2 Tbs melted butter
1/2 tsp salt
a little water
For the stuffing:
Set the peas and the potatoes boiling in separate pots.
Break open the cardamom pods and remove the small black seeds inside. Toss the cardamom seeds, cumin seeds and mustard seeds into a dry frying pan and toss over a medium flame until they begin to sizzle and crackle and smell good. Remove them to a mortar and pestle and grind them. Put a little vegetable oil in the frying pan and add the chopped onion, garlic and ginger. When the onions are limp and it all smells nice, add the ground spices. If the potatoes are done, continue. Otherwise turn off the heat to wait until potatoes and peas are cooked.
Remove the poatoes from the pot, reserving some of the water. Cut them in small cubes (just under a centimeter/half inch in size) and add them to the pan with the onion and garlic. Drain the peas and add them too. Add the rest of the ingredients and give a generous helping of salt. Add a little of the potato water (about half a cup) and cook down the mixture to let the flavors mingle. Taste for salt; it will need more than you expect.
Set aside to cool a bit while you make the pastry.
For the pastry:
Mix the flour and salt and drizzle the melted butter over them. Add the yogurt and mix thoroughly. If the dough remains too dry to roll out, add a little water. If it's a little too moist, add a little more flour. Knead for five minutes until it is smooth and very elastic.
To construct the samosas:
Pull a piece of dough a little larger than a golf ball from the lump. Roll it in your hands to get an even ball shape. Flatten it with your palm and lay it on a floured surface. Use a rolling pin to roll it out to a circle slightly larger than a woman's hand, fingers spread out (about 20 cm/7-8"). Cut the circle in half. Dampen your finger with some water (I kept a small bowl of water handy) and trace it along the cut edge of the half circle. Fold over the dough and pinch together where you just moistened it. When you pick up the dough, you will now have a cone that you can fill with the stuffing. Be generous and try to push the stuffing into every corner. The dough is a lot more elastic than I expected and can take a certain amount of abuse. When you have filled the cone, dampen the edges of the top and pinch them together to close the dumpling. Try to squeeze out any air from the inside as you go. Repeat until you have used all the dough and stuffing.
To cook, fill a small sauce pan two thirds of the way with oil or heat up your deep fat fryer. (I gave mine away when we moved, having used it once in seven years!) If you are using oil in a sauce pan, make sure it is on a very stable burner and do not over fill; the volume of the samosa will bring up the oil level when it is added. To test if the oil is hot enough, toss a small pinch of dough in it. If bubbles form around it and it immediately starts browning, the oil is hot enough. Carefully lower the first samosa in the oil. When it has turned a nice golden brown (about 2-3 minutes) remove and drain on paper towels. Repeat with the remaining samosas.
Serve these hot from the pan or (if you are entertaining) reheated in the oven with a variety of chutneys