In a large heavy-bottomed pot, heat the olive oil over medium-high heat.
2 Tablespoons extra virgin olive oil
Add the onion, and sauté for 3-4 minutes, until translucent.
1 medium yellow onion
Add the garlic, carrots, and potato, and sauté, stirring frequently, for about 5 minutes.
3 cloves garlic, 1 cup diced celery, 1 cup diced carrot, 1 large yukon gold potato
Add the rosemary, red pepper flakes, salt, and pepper, and sauté 1 minute more.
1 teaspoon finely minced rosemary, pinch red pepper flakes, 1 teaspoon fine-grain salt, ½ teaspoon freshly ground black pepper
Add the beans and vegetable broth.
3 (14-ounce) cans white beans, 6 cups vegetable broth
Increase the heat to high, and bring the soup to a boil.
Cover, reduce to medium-low, and simmer for 15 minutes, until the vegetables are tender.
Using an immersion blender, purée half the soup in order to make it thick and creamy. If you don’t have an immersion blender, you can transfer half the soup to a stand-up blender, and then return to the pot after blending.
Add the kale and lemon juice. Return the soup to the heat until the kale leaves have wilted.
1 small bunch Tuscan kale, 1-2 Tablespoons freshly squeezed lemon juice.
Serve hot, with extra lemon juice, pepper flakes, and a bit of freshly grated parmesan if desired.