Recipe from The Soup Peddler's Slow & Difficult Soups. Serves 6-8.
Ingredients
1 cup extra virgin olive oil
3 onions, chopped
2 potatoes, peeled and diced (I used Idaho potatoes)
3 large zucchini, diced
1/4 cup tomato paste
Juice of 4 lemons, or to taste
2 bunches cilantro, coarsely chopped, stems included
Salt (I used 1 tsp kosher salt)
Directions
Heat the oil in the bottom (where else?) of your soup pot over medium-high heat. The oil should form a deep puddle. Add the onions and sauté them slowly, longingly, until they are limpid, about 15 minutes.
Add the potatoes, zucchini, and tomato paste. Just barely cover with water, turn the heat to high, and cover. Once brought to a strong simmer, turn the heat down to medium-low.
When the potatoes are very soft and the zucchini has given itself to the soup, about 20 minutes, turn off the heat. Add the lemon juice and cilantro, and season to taste with salt. Using an immersion blender, purée the soup to a smooth consistency; alternatively, working in batches, pureé in a regular blender until smooth. The soup should shimmer in the ambient light.
Serve hot or cold.