Step 1

Soak both the lentils (urad dal/whole black gram and rajma/kidney beans) in water overnight or at least for 6 hours. This needs to be done only if you are using dry lentils.

Step 2

Add all the ingredients to the slow cooker (except cream and kasuri methi) along with four cups water. Stir well. Cook on high for 8 hours or low for at least 12 hours till the lentils are cooked through and can be easily smashed between your fingers.

Step 3

Mix well and lightly mash everything with the back of a ladle or spoon. Add the cream and kasuri methi if using and cook on low for another 20 minutes. Top with more butter and serve hot. If serving later, you can keep this on warm for up to 3 hours. Just thin with a little water or milk before serving if it's too thick.