Step 1

Heat half the ghee in a large frying pan over high heat. (Alternatively, use the Browning function on a slow cooker.) Cook the lamb, in batches if necessary, turning often, for 8 minutes or until browned. Transfer to the slow cooker.

Step 2

Heat the remaining ghee in the pan over medium-high heat. Add onion. Cook, stirring, for 10 minutes or until well browned. Add garlic. Cook, stirring, for 1 minute or until aromatic. Add curry leaves, garam masala, cumin, ground coriander, paprika, fenugreek and chilli. Cook, stirring, for 1 minute or until aromatic. Add the tomato paste. Stir until well combined. Add 60ml (1 ⁄4 cup) water and three-quarters of chopped tomato. Bring to the boil. Transfer to slow cooker. Cover. Cook on High for 5 hours or until the lamb is tender.

Step 3

Just before serving, heat the oil in a small frying pan. Add the cashews and cook, stirring, for 2 minutes or until lightly toasted. Add the extra curry leaves and cook, stirring, for 2 minutes or until crisp.

Step 4

Remove the lamb from slow cooker. Mash tomato mixture in slow cooker to thicken. Add the remaining chopped tomato. Season and stir. Return the lamb to sauce. Scatter over cashew mixture. Serve with rice, cucumber, yoghurt and chutney, if using.