Heat the oil in a large pan or in your pressure cooker pan until hot. Add the onion, celery, garlic and salami and fry for 5 minutes until soft.
Add the parsley, beans, tomatoes and chicken stock and stir.
Pop on the lid and cook under high pressure for 45 minutes.
Cook for anywhere between 2-3 hours over a low heat (covered) until the beans are fully cooked and creamy in texture. The cooking time depends on the type of beans you settle on - just cook 'em 'til they're done!
Using a stick blender, blend in one spot, without moving too much for 20 seconds so that the soup gets a little blended but not fully. This will make it a little creamier while still having texture. You could also just mash some of the beans with a fork.
Season well with lots of salt & pepper and serve.