Lentils and tomatoes are nutritious foods that blend well together to make a robust, earthy soup suitable for lunch or a light dinner. Lentils contain 24 g of protein per 100 g, making them a viable alternative to meat and an excellent food for vegetarians. In addition, one medium-sized tomato contains 45 percent of the recommended daily allowance of vitamin C and 20 percent of the recommended daily allowance of vitamin A. This recipe yields approximately four servings of tomato and lentil soup, but the recipe may be doubled to make a larger batch.
Combine the shiitake mushrooms with 1 cup of hot water in a small bowl and let it stand for 20 minutes or until soft. Remove the mushrooms from the liquid and transfer them to a cutting board. Strain the liquid through a sieve and set it aside.
Chop the mushrooms coarsely and place them in a small bowl for future use. Heat the oil in a small saucepan over medium heat, add the onion and garlic, and cook for about 7 minutes, stirring frequently, or until the onion is golden brown.
Add mushrooms, soaking liquid, tomatoes, salt, tarragon, ginger and 2 cups of water to the saucepan. Stir thoroughly, add the lentils and then heat the mixture to a rolling boil over medium-high heat. Reduce heat to low and cover.
Simmer the tomato and lentil soup for about 30 minutes, or until the lentils are tender. Remove the pan from the heat and serve immediately for the best flavor and texture, or store the soup in an airtight container in the refrigerator for three to four days.