Make a smooth paste by mixing chopped onions, cashews, and melon seeds in a blender.
Heat vegetable oil or ghee in a heavy bottom pan.
Add whole garam masala (cinnamon sticks, green cardamom pods, cloves, and bay leaves).
Fry for a minute until fragrant.
Add onion-cashew-watermelon seed paste and garlic paste and cook until the raw taste goes away.
Add red chili powder, chopped green chilies, cashew, and poppy seeds paste, curd, salt, and cook well.
Now add the marinated mutton and enough water.
After boiling, cover the lid and cook on low flame for about 45 minutes.
Add sugar and garam masala in it and keep cooking until the mutton becomes soft and the oil separates.
Season with salt to taste.