In a large stock pot over medium heat add oil and sauté the zucchini, onions, peppers and garlic until they just begin to soften, about 5-7 minutes.
Add the kidney beans, garlic, kale and spices - Italian seasoning, salt, pepper and red pepper flakes and continue sautéing for again for about 2 more minutes.
Next add the vegetable stock, tomatoes, tomato sauce and 2 cups of water. Bring to a boil, reduce to a simmer and loosely cover. Simmer on the stove for about an hour stirring occasionally. You may need to add more water to soup - just keep an eye on it. After an hour, check and adjust seasoning - you may need a bit more salt & pepper.
If you enjoy pasta in your Minestrone Soup cook it separately and add it to the soup before serving. If you cook them together, it will absorb all the sauce. Be creative and use your favorite vegetables, enjoy!
Notes
This meal can also be made in the slow cooker. Just add all of the ingredients, cover and simmer on low for four hours.