1. Start by chopping 1-2 onions (any kind) and frying in a little olive oil in a large casserole/soup pot. Add some chopped garlic. Then any of the following: chopped celery, chopped carrot, and chopped (raw) root vegetables--potato, parsnip, etc. Stir until the veg are softened.
2. Add some homemade stock. If you don't have homemade stock, then add a stock cube, gel or liquid with the appropriate amount of liquid.
3. Now is the time to add vegetables such as courgettes (zucchini), green beans, peas, corn, etc. Think non-leafy veg which grow above the ground. Cook until soft. Add canned or cooked beans, cooked chicken, meat, seafood.......The last things to go in are spinach, lettuce (yes!--the only way to use up lettuce that I know of), herbs, and cooked leftover veg including potatoes, etc.
4. You can season with spices, spice mixtures, herbs, coconut cream or coconut milk. Taste the soup using a new, clean spoon each time. If it tastes nice, then eat it. If not, then add something to give it zing.
5. I prefer to use a stick/immersion blender to blitz my soup a bit, but not completely smooth. Serve with your favourite accompaniments. (Sourdough bread with butter is our fave. But you can also use a dollop of pesto, croutons, toasted seeds, or even popcorn sprinkled on top).
(Today's soup was made using: 1 red onion, 1 white onion, 2 cloves garlic, tbsp olive oil, 2 carrots, 1 celery stalk, 1 can of corn, 1 courgette, 1 leftover baked potato, 1/2 head lettuce, 1 tin haricot beans, homemade chicken stock. We did not need additional flavouring because the stock was made from a roast chicken I made using a wonderful Middle Eastern Spice Blend. This soup really packed a punch.)
**Please note: Although this is a great way to use up excess or even old produce, do not use food which is moldy, or lettuce which is brown. These can be really hazardous to your health.