In a large soup pot heat oil over medium heat. Sauté garlic for a second then add onion. Stir until it starts to cook slightly translucent. Add the remaining vegetables and stir till they just cook and color.
Add Lentils, sauté for a second, and then add stock. Bring up to a boil then turn the heat heat down so it is at a simmer. Cook for roughly 20 minutes or even longer it doesn't matter you can't kill it.
Let cool a little and then dig in.
As always the soup is sooooo much better the next day and you can add other fun things. My Boyfriend, a def. non vegan but loves my cooking(the reason this American is living in South Africa), loves cilantro aka fresh coriander so I chop a little and top the soup with it and it is super yummy.
There must be a mess of lentil soups and this is really dependent on the right stock (believe me I've used yucky ones and a nice one makes such a difference). I hope this is helpful and whomever tries it enjoys it.
Cheers!