Boil 2.5 cups water in a saucepan. Add turmeric, garlic, peppercorns, onion, lentils and 1 ts salt. Bring to a boil again. Turn heat to medium-low and simmer until lentils are cooked and most of the water had dried up (about 20 mins). Mash or grind lentils completely using a little water if necessary. Return lentils to saucepan. Pour in 6 cups water and bring to a boil. Turn heat on to medium-low and simmer 10 to 15 mins. Add lemon juce and salt to taste. This soup can be eaten as is or with boiled rice.