- 1 tablespoon olive oil
- 1 large red onion, diced
- 2 carrots, diced
- 1 stalk celery, diced
- 4 potatoes, diced
- 10 (5 inch) zucchini, diced
- 1 leek, sliced
- 1 quart hot water
- 1 bunch Swiss chard, chopped
- 1 head Savoy cabbage, quartered, cored and shredded
- 1 bunch kale, shredded
- 2 (15.5 ounce) cans cannellini beans, drained and rinsed
- salt and ground black pepper to taste
- 3 tablespoons tomato puree
- 8 slices day-old bread
Place the olive oil in a deep pan and heat over medium-high heat. Stir in the onion, and cook until transparent, about 5 minutes. Mix in the carrots, celery, potatoes, zucchini, and leek. Stir and cook 5 minutes more. Pour in the hot water to cover the vegetables. Stir in the Swiss chard, Savoy cabbage, and kale. Cover, reduce heat to medium, and simmer for 1 hour.
Place 1 can of beans in a blender or food processor bowl. Blend until smooth. Stir pureed beans into the vegetable mixture along with the second can of beans. Season to taste with salt and pepper. Reduce heat to low, and simmer for 20 minutes, stirring occasionally. Stir in the tomato puree.
Prepare the soup by layering slices of bread with the vegetable mixture in a casserole or soup dish. Cover, and refrigerate for at least 8 hours, or overnight.
To serve the soup, place in a pot, and reheat over medium heat. Serve hot.