Serves 3-4, and makes a spectacular lunch with salad and a grilled cheese sandwich on the side.
1 Tbsp olive oil
1 small onion, diced
1 cup lentils
1 quart chicken stock (homemade or low-sodium storebought)
1 potato, diced
1 tomato, diced
1 cup water
Fresh ground black pepper, to taste
In a three-quart saucepan, heat the olive oil over medium heat. Add onion, and sauté for 2 minutes, until translucent. Add lentils and stock. Bring the stock to a boil, then reduce to simmer and cook, covered, for 10 minutes. Add potato, tomato, and water, and continue to cook until potatoes and lentils are cooked through. If you're using homemade stock, you may need to add salt at this point; if storebought stock (I use Swanson 99% Fat Free), you'll have plenty of salt in the soup. Season with lots of fresh black pepper to taste.