In a blender or bullet whiz, combine the olive oil, peanuts, onion, chilli, ginger, lemongrass, coriander, cumin, nutmeg, cinnamon, cloves, cardamom, fish sauce and sugar and whiz until a paste forms. If you need a little more liquid, use some of the coconut milk.
Turn on your slow cooker to auto. Add the diced beef and kumara. Add the Massaman curry sauce and the rest of the coconut milk and stir to combine. Cook for 6-8 hours until the beef is tender and serve with rice.
