I love lentil soup you can do anything you want but it goes particularly well with sweet things like apricots or squash.
Lentil and Apricot Soup
Sweat an onion, garlic and a big sweet potato in a little oil.
Add a few chopped, dried apricots along with a sloosh of tomato puree (or some chopped tomatoes, a couple of handfuls of lentils and spice of your choice (I like cinnamon, coriander and a touch of nutmeg) and season. Cover with water by about 2", bring to the boil, cover and simmer until cooked.
If it gets too dry you can always eat it as pate on toast
You can blitz it or part of it or leave it chunky, change the fruit and/or spices - apple and ginger is amazing too, or use different veg instead of the sweet potato.
There's something about a touch of sweetness with the lentils that makes them taste really rich.