Egyptian-Style Lentil Soup (from the Mediterranean Vegan Kitchen by Donna Klein) from Wendy

1 small red onion (about 4 ounces) sliced into very thin rings (optional)
4 tablespoons extra-virgin olive oil
2 medium yellow onions (about 6 ounces each) coarsely chopped
5 ounces (about 2 1/2 small) carrots, coarsely chopped
1 stalk celery, coarsely chopped
2 large cloves garlic, finely chopped 
1 1/2 teaspoons cumin seeds
1 teaspoon fennel seeds
4 cups vegetable broth (use the recipe posted above, or low sodium canned) 
4 cups of water 
1/2 cups of lentils, rinsed and picked over
1 small dried hot red chili pepper, left whole, or cayenne pepper to taste (optional) 
salt and freshly ground black pepper, to taste
juice of 1/2 large lemon (about 2 tablespoons) 
lemon wedges (optional) 

 Prehead the oven to 425F (220C). Place the red onion in a pan and toss with 2 T oil. Cover the pan tightly with foil and bake for 15 min or until  soften and fragrant. (For your health, I don't recommend using foil - use a lid instead) Remove from the oven an let stand, covered, until ready to use.

Meanwhile, in a large stockpot, heat the remaining oil over medium-low heat. Add the yellow onions, carrots, celery, garlic, cumin, and fennel seeds and cook, stirring occasionally until the vegetables are tender, about 15 minutes. Add the broth, water, lentils and chili if using, season lightly with salt and pepper. Bring to the boil over medium-high heat. Immediately reduce the heat partially cover, and simmer gently for 30 minutes, stirring occasionally. 

Uncover and simmer for 15 more minutes, stirring occasionally or until the lentils are very tender and the broth is slightly thickened. Remove and discard the chili. Stir in the reserved red onion and the lemon juice. Season with additional salt and pepper as necessary. Serve hot, passing the lemon wedges separately if desired.