Our red lentil soup is a simplified spin on a Goan staple. Split red lentils, the foundation of the dish, cook in minutes, making this a quick weeknight meal. The blend of coriander, fennel and turmeric capture the essence of the dish's complex spicing without requiring the cook to pull out half the spice cabinet. A shot of lime juice cuts through the starchiness. Fresh ginger added welcome brightness and adding a portion of it at the end kept the flavor vibrant; grating the ginger on a wand-style grater was best. If you can’t find ground fennel, grind whole seeds in a mortar and pestle or a spice grinder. Both virgin and refined coconut oil worked, but virgin had a slightly stronger flavor. Yellow and brown mustard seeds both were good.