Cover lentils with 1 cup water. Bring to a boil, simmer until lentils are tender. 

Meanwhile, sauté onions in a skillet with 1 tbsp. olive oil until browned. Add mustard seeds, turmeric and chopped chile. Sauté until seeds start to pop. Add to lentils with garlic and ginger, cook for 15 minutes, stirring occasionally. Add additional water to make the consistency of soup. Add tamarind bar, stir to combine flavors. Add salt to taste. Serve with cilantro garnish.