Here I am presenting before you one of the methods of mutton curry that I have succeeded after conducting experiments with different ingredients in different proportions and finally got it right. If done in patience using correct proportions and taking sufficient time, it will get better results.

Ingredients
Mutton cut into pieces - 1 kg
Shallots sliced very thin - 1/2kg
Ginger - a medium piece
Garlic - 1
Green chillies-2
Sambar(Thondan) chilli - 4 (taken as a whole)
Turmeric powder - 1/4 tsp
Kashmiri chilli powder -  1 tsp (or as per taste)
Fried coriander powder - 2-2.5 tsp
Garam masala - 1/2 tsp
Cloves, pepper, cardamom, cinnamon, fennel seeds - A handful
Coconut oil - as needed
Red chillies - 2 or 3
Curry leaves - As needed
Tomato - 1
Salt - to taste

Method of preparation
1. Put garlic, ginger and green chillies in a mixer just to blend it.
2. Heat a karahi(kadai). Add oil, mustard and red chillies. When mustard splutters and red chillies change the colour add ginger-garlic-chilli mixture.
3. When it turns light brown colour, add curry leaves, shallots and sambar chillies. Cook it till shallots becomes tender and turns to light brown colour.
4. Add turmeric powder, freshly cut tomatoes and cook the ingredients 5-7 more minutes.
5. Add chilli powder, coriander powder, masala powder and a half glass of water. Stir the contents well and close the kadai with a tight lid.
6. When it begins to boil, reduce the flame and wait for 5 more minutes.
7. Add mutton pieces, stir well and close the lid tightly. Let it be so for 1 hr. Never open the lid frequently. If so, your curry will loose its flavour. For the whole time of preparation, don't open it more than 3 or 4 times.
8. After 50 minutes, add salt and stir well. Close the lid and cook in low flame for another 15-20 minutes, may be up to half hour.
9. Crush the masala and add to the curry and wait for another 5 minutes.
10. Add a little coconut oil. You can add a little curry leaves also, if you want. Never stir now. Close the lid at once and put the flame off.
11. After 5-10 minutes, open the lid and stir the contents well. Your curry is ready to serve.

Note: For a variety, you can cut a small tomato into small pieces and it can be added along with a chopped chilli when you add crushed masala. Also, if you exclude adding coconut oil in the last part, it gives another flavour and taste to the curry. You can use any of these 3 alternatives at the time of finish. You can also use chicken instead of mutton. In both cases, cook it for minimum one hour in lowest flame. It will add more taste. Also, never add water later for this preparation.  Good quality kadai must be used for this preparation. Otherwise it will be difficult to cook mutton without water.

Sambar chilli used for its preparation is given in the picture above. It gives a unique taste and aroma to your dish. But this chilli is found only in southern districts of Kerala and Tamil nadu.Always use it as a whole without removing its stalk. You can also exclude this chilli from this preparation. This curry is a best combo for any type of Indian bread.