Spanish Chorizo and Chickpea Soup

It is rainy and freeeezing outside so I decided we should have soup tonight.  This recipe is from Rachel Allen's cookbook.  Maybe it's because she is Irish, but I love making her recipes when it is a wet day outside.

1 tablespoon olive oil
5oz chorizo, diced
1 onion, peeled and finely chopped
2 celery stalks, finely chopped
2 cloves of garlic, peeled and crushed
1 (400g) can of chickpeas
2 (400g) cans of chopped tomatoes
1 liter (1 3/4 pints) chicken stock
9oz fresh spinach, destalked and chopped or baby spinach leaves left whole
Salt and pepper

Cook the diced chorizo in olive oil for about 2 minutes until the chorizo releases it's oils.  Add the chopped onion, garlic and celery.  Cook on medium-low heat with the lid on for about 10 minutes (until the onions are slightly brown).  Add the chickpeas and their liquid, chopped tomatoes and the stock.  Season with salt and pepper and bring to a boil.  Simmer for about 30 minutes.  Season with more salt/pepper if necessary.  Add the spinach about 2 minutes before serving (place lid on pot after adding).  Stir in the wilted spinach and serve.