the concept behind the soup is that it be fully *alive*. The first 'food' after the Master-Cleanse should be loaded with vitamins and minerals, and have the care that you have given it. This is no small thing, puting energy and intention in what you do. No matter how "healthy" these bottled soups are, they would be dead by comparison to what you can make.
So, since this is a cleansing fast, go the extra distance. It's very easy. You take the best few veg. you can find, including potatoes, (which are loaded with potassium) and whatever else appeals to you. As you get closer to completion, you'll know what you
really want--what the body really wants.
You simmer these in good water, leave the lid on to retain the goodness, add good Sea Salt , maybe some tamari, a squeeze of lemon, then strain out the veg. leaving you with a pure life-giving broth. This will be NOTHING like what you could buy prepared.
You'll be amazed at the flavour. Then, later you have some more, eat a few of the vegetables...and so on.
The better your beginning- your return to food is, the more value you will take away from this MC. As they say "you're worth it."