Bring the dry lentils, liquid and vegetables (except for red pepper) to a boil on high heat, then simmer for 1 hour on low heat or until the lentils are tender.
Add the remaining ingredients and simmer another 15-25 minutes, stirring occasionally.
If desired, blend 1-2 cups of the soup and return it to the pot for a richer, fuller flavor (I didn't do this, but it would have been good).