Place the chicken thighs in the slow cooker.
Fry the onion in the ghee over a medium heat for about 5 minutes, or until the onion has browned slightly.
Add the garlic to the onion, and fry for a further 2 minutes.
Spoon the onion mixture over the chicken in the slow cooker.
Add the lime zest and juice, cumin and ground coriander to the slow cooker.
Separate the leaves of the fresh coriander from the stems and roots.
Roughly chop the coriander leaves, place in a small bowl, cover with cling wrap and set aside in the fridge.
Finely chop the coriander stems and roots, and add to the chicken in the slow cooker.
Season with salt and pepper, then stir well.
Cook on low for 6-8 hours, high for 3-4 hours, or until the chicken falls away from the bone.
Once cooked, remove the chicken thighs from the slow cooker, reserving the liquid.
Shred the meat and discard the bones.
Place the shredded chicken back in the reserved cooking liquid and add the reserved coriander leaves.
Check the seasoning, adjusting if necessary, then stir the chicken through the reserved liquid.
Use immediately as desired, or allow to cool then freeze.