1) Rinse lentils until no more foamy water comes from them. If the red lentils are thin saucer shape, no soaking before cooking is required. But if the red lentils are more round in shape rather than flatish, soak the lentils for 30 minutes.
2) Meanwhile, place first five ingredients in a saucepan and cook on medium-low heat until tender, about 45 minutes. Remove from heat and let cool.
3) Add tomato paste to 1/4 cup water. Mix cumin in as well, and add to cooling soup mixture.
4) When soup mixture is cool (if it is still hot, be extra careful and blend slowly or it could shoot out of the blender), puree in blender or food processor until smooth. Transfer to a saucepan and heat. Add salt or soup base to taste and more stock if a thinner soup is desired.
5) Cut pita bread in wedges, brush lightly with olive oil and toast in oven until crisp, or use purchased pita chips.
6) For an extra touch (but optional), mix olive oil (or butter), lemon juice, paprika, and cumin together and swirl it on the top of the bowls of soup prior to serving.
7) Squeeze lemon juice and add pita chips to each bowl just prior to serving. The soup requires lemon but the lemon ruins the soup if it is added and then left to sit overnight. Offer lemon wedges and pita chips at the table for those who want more lemon.