Start by soaking your green lentils in water while you chop the carrots, celery, garlic, onion, and leek. Once these initial vegetables are prepped, heat olive oil in a stock pot over medium-high heat. Add the diced vegetables and cook until the onion and garlic soften, about 7 minutes. While they cook, chop your kale; the spinach leaves can stay whole for later.
Once the vegetables are softened, drain the lentils and add them along with the rice to the pot. Give everything a good stir, then pour in the vegetable broth and water. Now, add the chopped kale, whole spinach leaves, and all the spices: chili powder, cumin, thyme, oregano, cayenne, sea salt, and cracked pepper. Turn the heat to high to bring the soup to a boil, then reduce to low, cover, and let it simmer for 25 minutes.
After the initial simmer, remove the cover and continue to cook the soup on low for another 30 minutes. Taste the soup and adjust the seasoning; I found it balanced with an additional 1/2 tsp of salt and a bit more pepper. Once the lentils and rice are tender, the soup is ready to serve.
