In a high-speed blender, add the carrots, jalapeno, ginger, and garlic and blend until everything is roughly chopped, scraping down the sides as needed. Add the onion and blend again, scraping down the sides and under the blade as needed, until no large chunks remain.
In a large pot over medium heat, warm 2 tablespoons oil. Add the onion mixture and ½ teaspoon salt and cook, stirring occasionally, for 5-7 minutes.
Push the aromatics to the edge of the pot and add another 1 tablespoon oil into the center and pour the spices into the oil and stir them around for about 30 seconds (the oil will help bloom the spices!).
Add the water, tomatoes, lentils, rice, and remaining 1 teaspoon salt. Use your hands (or kitchen shears) to break the tomatoes open and into smaller chunks (be careful of splatter). Stir everything together, then cover and bring to a boil over high heat. Stir again, then simmer, covered, for 20 minutes or until rice and lentils are cooked through, stirring halfway through. Stir in the lime juice and greens until wilted. If the soup is too thick for you, stir in some water to thin it out.
To make the salted yogurt (if using), in a small bowl, mix together the yogurt, lime, and salt.
Serve topped with salted yogurt (or plain yogurt + salt), cashews, and cilantro.