You could make this stew with any kind of lentil. The advantage of using the small, almost round green kind called French (or Puy), as chef Fernanda Milanezi does here, is that they hold their shape very nicely even when fully cooked. Slideshow: Lentils
How to Make It
Preheat the broiler. In a large saucepan, heat 2 tablespoons of the oil. Add the onion, celery, garlic and bay leaf and cook over moderate heat until softened. Add the lentils, tomatoes and stock; bring to a simmer over moderately high heat. Cover, reduce the heat and simmer, stirring occasionally, until the lentils are tender but still hold their shape, 45 minutes.
Meanwhile, set the eggplants on a foil-lined baking sheet and rub with the remaining 2 tablespoons of olive oil. Broil 6 inches from the heat, turning occasionally, until completely blackened and tender, about 20 minutes. Let cool.
Cut the eggplants in half lengthwise and scoop the flesh into a colander set over a bowl; discard the skins. Let the eggplant drain for 5 minutes, then transfer to a bowl and mash until smooth.
Stir the harissa and half the eggplant into the lentils until warmed through. Stir in the 1/3 cup of chopped parsley and season with salt and pepper. Ladle the stew into bowls; top with the remaining eggplant. Garnish with yogurt, chopped walnuts and parsley, mint leaves and a drizzle of pomegranate molasses and olive oil.