Bok choy soup

After a weekend of indulgence, I was happy to feed me and others this light but satisfying soup.

Recipe by Gray Apron
time: 30 minutes

 ingredients 
1 bok choy head, shredded
1 medium onion, peeled and chopped
2 medium carrots, peeled and diced
2 celery stalks, chopped
3 Tablespoons olive oil
1 teaspoon dry thyme
1 small can crushed tomatoes
1 Parmesan rim (about 1 oz/28 g)
4 cups (1 l) vegetable stalk (or water with 2 teaspoons salt), boiling
salt, pepper to taste

 instructions 
In a large pot, heat oil on medium/high. Add onion, carrots, celery, thyme and sauté for 5 minutes. Add crushed tomatoes and Parmesan rim, sauté for 2 minutes. Add bok choy, sauté for 5 minutes. Pour in boiling liquid. Lower the heat. Simmer for 15 minutes with a lid ajar. Adjust seasoning and serve.

NOTES NOTES NOTES NOTES NOTES NOTES NOTES NOTES NOTES

• I've never cooked bok choy before, but the vegetable looked so good in the store, I saw soup in the making right away;
• the Spring, local growth it less wrinkled and more green than what I saw in the Winter;
• bok choy is much milder in taste than cabbage;
• I originally prepared 8 cups of the stalk, but I used only half; I like my soups thick.