Step #1 In a large soup pot, saute the onions on medium-low until soft.
Step #2 Add the minced garlic & saute until fragrant, being careful not to brown it.
Step #3 Add the dried lentils, basil & oregano & saute a little longer, until fragrant.
Step #4 Stir in the can of sliced tomatoes & add water or chicken stock to cover the beans about 1 or so inches, depending on how thick you want the soup.
Step #5 Add brown sugar, red wine vinegar & carrot, if using.
Step #6 Boil the soup until the lentils have softened to a satisfactory texture.
Step #7 Add water/stock if necessary.
Step #8 Remove approximately 2 c of soup and, using a handmixer or foodprocessor, purify the soup.
Step #9 Add the sour cream to this mixture, stir until smooth & and return to main pot.