Wild rocket, pear and cheese soup

This term Eddie is studying ancient Rome at school. We talked about foods they ate in the Roman empire, and I mentioned that rocket was one of the edible leaves they favoured.
While checking out the Sunday bargains at Waitrose earlier today, I've spotted a bag of wild rocket reduced to 25p and decided to cook soup for dinner. It is by no means a Roman recipe, especially that I use a potato in this soup, which obviously wasn't known in Europe until the 16th century.
But wild rocket would have been widely used by the Romans in salads, soups and stews.

I had a good rummage in the fridge to see which other greens and other veg I can find, and got half an onion from the day before when I fried potatoes with mushrooms, a few celery stalks, half a bag of spinach, and a handful of baby courgettes which were slightly past their best.
I also had a small chunk of cheese (Petite Basque, I think).

It reminded me of Three men in a boat and how they cooked an Irish stew, when they were putting all kinds of odds and ends together. This used to be one of my favourite books in early teens, though I haven't re-read it since then.

Wild rocket, pear and cheese soup
Ingredients:
1/2 medium white onion
2tbsp olive oil
1 clove of garlic
1 medium potato, peeled and chopped
1 long celery stalk, chopped
about 80g of courgette
1 pear, peeled and chopped (I used a Conference pear)
1 bag of wild rocket (90g)
1/2 bag of baby spinach (about 60g)
a small chunk of cheese (about 50g)
1 cube of vegetable stock
sea salt

Finely chop half an onion, and fry it with olive oil for about 5 minutes, until golden brown. Add a finely chopped garlic and fry for another minute. Peel and chop one potato, and put in a pan with a stock cube, add the celery, courgette and pear, as well as onions and garlic, and pour enough water to cover all the vegetables. Cook for about 20 minutes, add rocket and spinach and grated cheese and cook for another 5 minutes. You might want to add more water if the soup is too thick.
Once cooked, blitz the soup with a hand blender and serve hot, with a spoonful of single cream, Greek style yogurt or soured cream (optional).
This is a tasty vegetarian soup.
For a vegan version, skip the cheese and any other dairy.

Adding this recipe to #KitchenClearout linky hosted by Cheryl at Madhouse Family Reviews, since like George from Three men in a boat I've added all sorts of odds and ends to this soup.