Clean and cut 500 grams of mutton into medium-sized pieces.
In a bowl, mix the mutton pieces with 200 grams of yogurt, 1 teaspoon of ginger-garlic paste, 1 teaspoon of red chili powder, 1/2 teaspoon of turmeric powder, and salt to taste. Marinate for at least 30 minutes.
Heat 4 tablespoons of oil in a pressure cooker or heavy-bottomed pan. Add 1 finely chopped large onion and sauté until golden brown.
Add 1 teaspoon of ginger-garlic paste and sauté for 2 minutes.
Add 2 chopped tomatoes and cook until they turn soft and mushy.
Add 1 teaspoon of coriander powder, 1/2 teaspoon of cumin powder, 1/2 teaspoon of garam masala, and 1/2 teaspoon of red chili powder. Cook for 2-3 minutes until the spices are well-blended.
Add the marinated mutton pieces and cook on high heat for 5 minutes, stirring occasionally.
Add 1 cup of water, cover the pressure cooker or pan, and cook until the mutton is tender (approximately 4-5 whistles in a pressure cooker or 45 minutes in a pan).
Once the mutton is cooked, garnish with chopped coriander leaves and serve hot with rice or roti.