The pan of the slow cooker you can use on the stove

Heat oil and whole spices for couple of minutes then add the chopped onions and brown till light brown

Add tomatoes or passata (I prefer passata) and all the spices and the garlic and ginger and green chilli paste

Normally when you cook on the stove you would need to let the tomatoes and spices cook but as this is going in the slow cooker you can just add the lamb (potatoes also at this point if you want them) & put it straight into the slow cooker

Add 1 cup of water mix and set your slow cooker. On high for 4 hrs/medium for 6/low for 8hours depending on you time

I normally do 6 hours on medium. And I stir half way through

Finally add the coriander and Garam masala.. serve hot with rice naan or chappati