Asparagus soup with ham 'croutons'

500 grams asparagus, woody bits removed
500 ml vegetable stock
4 tablespoons cream - or thick yoghurt
a handful spinach chopped
one onion, finely chopped
salt and pepper
1 tablespoon butter
diced bacon or ham

Fry the bacon or ham in the butter. Once crispy, remove, and put on a piece of kitchen towel to remove any excess oil. Keep the fat in the pan.
Set aside some asparagus tips for decoration and chop the rest into 2cm lengths.
Fry with the onion in the bacon fat.
Add 100 ml of the stock and simmer for 10 minutes. Add the spinach and remove from the heat.
Using a hand blender, blend the mixture into soup adding more stock if necessary. Add the cream and heat till almost boiling. Add more stock as necessary and remove from the heat.
This is delicious hot or cold, served with some of the cream - or yoghurt, the bacon and the asparagus tips. Also delicious hot with a freshly poached egg dropped in.