Peel and chop an onion, a couple of cloves of garlic (I like very garlicy food so I use 4 cloves but it's all down to personal taste) and two chillis (again it depends on how hot you want your soup to be - I used two habaneros and the final flavour is quite mild, try experimenting).
You don't need to be too delicate with your chopping as the soup gets blended at the end!
Saute in a good glug of olive oil in a large saucepan - I suppose it's about two tablespoons I use - until the onion is translucent. Keep stirring and don't get the heat too high, browned bits show the pan is too hot. If you get them it's not a disaster, just turn the pan down a bit!