Wash lentils thoroughly. Place in a saucepan with the turmeric & 5 cups of water. Bring to a boil, stirring often. Reduce heat & simmer, partially covered, for 25 minutes. Stir occasionally. Add lemon juice to lentils & cook for a further 15 minutes. Turn off heat & beat with a wire whisk.
Heat ghee, when very hot, add cumin seeds & fry for about 10 seconds. Remove pan from the heat & add red pepper & minced garlic. Stir rapidly for 10 seconds until the garlic begins to colour, but do not let it brown. Pour over the hot puree. Serve immediately.