Red Lentil Soup with Lemon

4 Tbsp. olive oil, plus additional good oil for drizzling
2 large yellow onions, chopped
4 garlic cloves, minced or pressed
2 Tbsp. tomato paste
2 tsp. ground cumin
? tsp. kosher salt, or more to taste
A few grinds of freshly ground black pepper
Pinch of cayenne or Aleppo pepper, or more to taste
2 quarts chicken or vegetable broth
2 cups red lentils, picked through for stones and debris
2 large carrots, peeled and diced
Juice of 1 lemon, or more to taste
1/3 cup chopped fresh cilantro


In a large pot, warm the oil over medium-high heat until hot and shimmering. Add the onions and garlic and cook until golden, about 4 minutes. Stir in the tomato paste, cumin, salt, pepper, and cayenne, and cook for 2 minutes longer. Add the broth, 2 cups water, the lentils, and the carrots. Bring to a simmer, then partially cover the pot and reduce the heat to maintain a gentle simmer. Continue to cook until the lentils are soft, about 30 minutes. Taste, and add more salt if necessary. Using an immersion or regular blender, puree about half of the soup. It should still be somewhat chunky, not completely smooth. Reheat if necessary, then stir in the lemon juice and cilantro. Serve the soup drizzled with good olive oil and dusted very lightly with cayenne, if desired.