Put onions in the pot with 2 cups of water and the salt. Cook on low while covered until the onions become see through which should take 45 minutes.
Add in the pepper, zucchini, rest of water, basil and garlic powder, cover and bring to a boil. Then lower it to a simmer for half an hour.
Put into a food processor or blender and blend then serve. Blend to the level of chunkiness you want, longer will be more smooth and shorter will be more chunky.
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