1 medium onion, diced
1 carrot, roughly chopped
1/2 yellow bell pepper, sliced
3 or 4 leaves of cabbage, sliced
5 cups of water
1 1/2 tablespoon grapeseed oil, or oil of preference
1 tablespoon shoyu sauce
1/4 teaspoon molasses
Salt to taste
Heat 1 tablespoon of grapeseed oil on a pan
Add onion and let it cook for 2-3 minutes
When the onion starts to become transparent, transfer them to a soup pot
Add carrot, yellow bell pepper, cabbage, water, shoyu sauce and molasses and 1/2 tablespoon of grapeseed oil
When the water starts to boil, turn down the heat to let the soup simmer for 20 minutes (or more if you have the time)
For soup stock, you could actually use any vegetables of your preference. However, to ensure that your stock is aromatic, try to use a minimal of carrots, celery and onion. These 3 vegetables are the basic ingredients for making mirepoix, which is a flavouring base for sauces, soups, stews and meat dishes.
You could stir fry the vegetables initially for more aroma but if you are lazy like me, you could just boil everything.
To keep the soup stock for future use, I pour them into ice cube tray and store them in the freezer.