Scrub your mussels and tap each one hard on the counter top. Discard any that open.
Place your coconut oil in the blender with the garlic, ginger, shallot, chilli and lemongrass. Blend to a paste.
Heat up the paste in a pan fry it gently for a few minutes. Add the coconut milk, cumin, cayenne, turmeric and fish sauce and bring to simmering point.
Add the mussels and cook with the lid on, stirring occassionally for 7-10 minutes. Since these green oki oki ones are larger than usual they make take some time to open. Discard any that have not opened after 10-12 minutes. Salt to taste and serve.