place potatoes in the slow cooker
heat a frying pan and brown meat in small batches
transfer to slow cooker
add massaman paste, coriander stalks and gingger to fry pan
tip in coconut milk and bring to boil
season with sugar, lime zest and fish sauce, lime leaves
pour over meat and potatoes
cook on low for 8 hours
spoon off excess fat from curry
add lime juice and fish sauce (if needed)
scatter coriander leaves and peanuts