From Vegetarian Times
2 tablespoons olive oil, divided
2 tablespoons yellow mustard seeds
2 teaspoons whole cumin seeds
3 tablespoons minced fresh ginger
3 cloves garlic, minced
sea salt to taste
1 medium red onion, chopped
½ cup golden raisins
1 cup brown lentils, rinsed and drained
3 ½ cups vegetable broth
½ lb. rhubarb, cut into ¼-inch slices
6 cups baby spinach leaves
½ cup chopped cilantro
Heat 1 tablespoon oil in cast iron skillet over medium-low heat. Add mustard and cumin seeds. Cover skillet, and cook 1-2 minutes, or until seeds begin to pop. Cook 1 to 2 minutes more, or until popping stops, shaking skillet often. Stir in ginger and garlic, and season with salt and cayenne. Cook for 1 minute. Cover, and set aside.
Heat remaining oil in saucepan over medium heat. Add onion and raisins and sauté 10 minutes, or until onions begin to brown. Stir in lentils and 3 cups broth; bring to a boil. Reduce heat to medium-low; simmer 25 minutes. Stir in rhubarb and remaining 1/2 cup broth; cook 6 minutes. Add spinach, cover, and cook mixture 6 minutes more. Stir mixture to incorporate rhubarb and spinach leaves, then stir in spice mixture. Serve garnished with cilantro.