Peel the potatoes and cut into bit sized pieces.
Put the potatoes in a saucepan and cover well with water
Put the saucepan on the stove and parboil the potatoes i.e. till they have just started to soften. This should take about 10 minutes once the water starts boiling. You can test how ready the potatoes are by gently pushing a thin wooden skewer (a satay stick is good) or the point of a sharp knife into the potato flesh. It should be easy to penetrate but have a little resistance.
While the potatoes are cooking, peel and slice the shallot or onion very thin.
Slit the chili along its length and slice it thinly across its width. You can remove the seeds if you like to reduce the 'heat' of the dish.
Strip the leaflets of the curry leaves from the stem.
Crush the garlic in a press or mortar or on a cutting board. If you use a mortar or board, add a little salt as you crush the garlic.
Pound the Maldive fish or dried prawns in a mortar or on a board till it's a rough powder. Maldive fish is tough so it takes a bit of pounding. You can use a spice grinder if you have one.
Chop the tomato into small chunks. For this dish I like to first quarter the tomato and remove the seeds and inner flesh. It makes for a drier finish to the dish.
Put the oil in a frypan on the stove and let it heat up for 1 - 2 minutes.
Add the onions and sauté gently till they start to soften.
Add the chili and the curry leaves and sauté for 1 - 2 minutes. Be careful: curry leaves spit, so stand back when you add them.
Add the mustard seeds, crushed garlic, Maldive fish or dried prawns, turmeric and chili flakes and sauté for a further 1 - 2 minutes.
If you haven't mixed salt with the crushed garlic previously, add a pinch of salt to the frying pan.
Drain the parboiled potatoes and let them dry off for a minute or two.
Add the chopped tomato to the frying pan and let it cook for a couple of minutes.
Add the potatoes to the frying pan. Using a spatula, gently mix the potatoes with the spice mixture in the frying pan, coating the potatoes in the gravy. Be gently, you don't want to mash the potatoes as you do this. Using the spatula to lift and flip the potatoes.
Let the potatoes cook in the gravy for a minute or two and then gently again with the spatula turn them through the gravy again.
Keep doing this for 5 minutes and then test the potatoes again with a skewer. It should go easily well in to the potato now. If not, keep cooking for a couple of minutes more.
Serve as a side dish with rice and curry or on its own with flat bread or roti.