Adasi: Persian green lentil soup with golden onions

Ingredients and method

Ingredients

• 200 grams dried whole green lentils (about 1 US cup), picked over and rinsed
• Water for soaking, plus 5 US cups freshly boiled water for the soup and more as needed
• 2 medium yellow onions, finely chopped
• 1 large yellow onion, thinly sliced, for the topping
• 4 tablespoons vegetable oil, divided
• 2 tablespoons unsalted butter
• 1 1/2 teaspoons tomato paste
• 1 teaspoon ground turmeric
• 1 teaspoon ground cumin
• 1/2 teaspoon ground black pepper
• 1/2 teaspoon fine salt to start, then adjust to taste
• Fresh lemon wedges for serving, optional

Method

1. Cover the lentils generously with water and soak for one to two hours in the refrigerator. Drain and rinse.
2. In a soup pot, soften the chopped onions in two tablespoons oil over medium heat. Stir regularly until golden, about 15 minutes. Add butter, tomato paste, turmeric, cumin and pepper; stir for about two minutes without scorching.
3. Add drained lentils, five cups hot water and salt. Bring to a simmer, cover and cook until lentils are tender, checking after 30 minutes. Add water if the mixture dries before the lentils soften.
4. Meanwhile, soften the sliced onion in the remaining two tablespoons oil in a skillet, stirring until golden. Lower the heat as needed so it does not burn; lift the topping out with a slotted spoon.
5. Take the soup off the heat. With the pot stable, use a potato masher to crush some lentils directly in the soup, leaving plenty whole. Return to a gentle uncovered simmer for about 15 minutes, stirring and adjusting with water to a spoonable consistency. Taste for salt. Top bowls with golden onions and serve with optional lemon.