In soup pot, saute
onions, garlic and ginger in butter until dark brown. Add coriander,
cumin, turmeric, and garam masala. Saute one to two minutes
more. Add tomatoes, lentils, and water, cover and bring to
a boil. Lower heat to medium low and cook until lentils are
almost done [about one hour].
Add carrots, mushrooms, and salt, cook until carrots are
done. Set aside a few sprigs of cilantro for garnish. Wash
and chop the rest, using some of the stem. Put chopped cilantro
into the soup and use cilantro sprigs to garnish each bowl
when served.