Cut broccolis, celery, onion, carrots into chunks.
Heat up oil in a stock pot.
Stir fry onions, then add celery, carrots and broccolis.
Add in stock. Bring to boil and simmer till carrots are soft (around 30min).
Add spinach. Bring to boil till spinach are soft (around 5-10 min).
Blend the soup in the pot until creamy.
Bring the soup back to a boil.
Add salt to taste and turn off heat.
Serve hot with a drop of sour cream, crushed roasted walnuts and black pepper.