Wash kale and remove the stems from the leaves. Rollup kale leaves and cut into thin ribbons. Set aside.

In a 4-quart soup pot, heat olive oil and sauté the garlic briefly over medium heat. Add about half of the cooked beans and part of the stock. Puree the rest of the beans and stock in the blender along with the tomato paste and sage. Stir the pureed beans into the soup. Add salt and pepper to taste.

Mix the kale into the soup and simmer until kale has wilted (about 10 minutes).

Add the lemon juice and enough water to make the soup a desirable thick consistency. Taste for salt and pepper and adjust seasonings accordingly.

Serve the soup topped with grated parmesan cheese (optional).