Red Lentil Soup with Potato and Lemon

Turkish red lentil soup, called kırmızı mercimek çorbası, is a classic dish and a ubiquitous offering in Turkish eateries. There are many versions of the soup, some with a base of chicken stock, others made vegetarian; some that include only with lentils plus a few aromatics, others fortified with rice. Istanbul home cook Emine Nese Daglar, and grandmother of chef Cagla Gurses, taught us her pressure-cooked version, which we adapted for conventional stovetop simmering. To add flavor and color, she uses a Turkish pepper paste called biber salçası; as a substitute we find tomato paste plus roasted red peppers work nicely. She also blends her soup to a smooth, elegant puree, as is traditional, but we prefer to keep ours rustic in texture. Lemon juice is an essential ingredient in kırmızı mercimek çorbası. It brings a brightness that balances the earthiness of the lentils.