Wash and put Rajma in the slow cooker overnight (add 4 times water & salt). In a pan, add oil, jeera seeds, Garlic & ginger, onions and salt. Cook the onions till they are brown. Now add all the spices and cook for 1 minute and then add tomatoes and cook till it sheds oil.
Now blend the tadka and again mix it with rajma in the slow cooker. Alo add Crushed chilli and flaked garlic at this stage.
(Add boiling water for desired consistency) then simmer for 30 minutes finish with green coriander.