Place everything in the slow cooker. Cook on low all day, for 8 hours or more. When cooked and falling off the bone, take out the lamb from the slow cooker. Roughly shred the meat and remove it from the bone. Discard the bone and return the shredded meat to the slow cooker. Keep warm until ready to serve.
Step 2
Heat the oil in a large saucepan on low to medium. Add the sliced onions and stir gently until softened and lightly browned. Add the ginger and stir until warmed. Add the remaining ingredients and stir to combine. Bring the liquid to a rapid simmer, then lower the heat and cook gently, covered, stirring occasionally, for at least 30 minutes. Continue cooking until the dried lentils have dissolved into a puree.
Step 3
Either serve immediately, or allow to cool before refrigerating, then warm gently when ready to serve.