Heat the coconut oil in a large, heavy soup pot over medium heat. Add the onions and lower heat until they are sizzling kind of quietly. Once the onions are a bit soft and translucent, add the cinnamon, cumin, coriander and chili flakes. Slowly sauté and stir this mix until the onions are really, really soft, about 6-7 minutes. Add the garlic and sauté until fragrant, about 1 minute.: Expect a gentle shush as the coconut oil warms and the diced onion begins to soften; the sound moves from a louder sizzle to a low, steady whisper as moisture releases. You will see the edges of the onion go translucent and the pieces collapse slightly, signaling they are ready for spice; the air will fill with the toasted, warm scents of cinnamon , cumin , and coriander , which is when the dish really starts to smell like Morocco. Add the chili flakes sparingly so they do not dominate. When you stir in the minced garlic , it should bloom quickly and perfume the pot but not brown; garlic overcooked will taste bitter, so reduce the heat if you see browning. A common misstep is rushing this stage with high heat, which scorches both onion and spices and creates an acrid base, so keep the temperature moderate and stir often to coax out sweetness rather than caramelizing hard edges.
Add the chopped dates, carrots and sweet potatoes. Season with salt and pepper. Stir to coat the vegetables in the spices and oil. Add the tomatoes and stir. Add the vegetable stock. Bring the soup to a boil and simmer until the sweet potatoes are just tender, about 10-12 minutes.: When you add the chopped Medjool dates , carrots , and 1 inch pieces of sweet potato , the pot will become visually brighter and the texture contrast increases. Coat every piece by stirring so the spices cling, and you will notice the dates begin to break down and lend a glossy sheen to the liquid. Pour in the canned crushed tomatoes and watch the color deepen to a warm, rich red; then add the vegetable stock and raise the heat until small bubbles appear and the surface moves steadily. Once it simmers, the aroma will shift from toasted spices to a rounded, savory stew scent. Check the sweet potatoes for tenderness by piercing a piece with a fork; it should give with little resistance. Avoid a rolling boil which can shred the vegetables and toughen them; maintain a gentle, steady simmer for even cooking. If the pot reduces too fast, lower the heat and add a splash more stock.
Add the chopped yellow peppers and chickpeas and stir the soup. Season the whole thing again with salt and pepper. Simmer until the yellow peppers are tender and the sweet potatoes are quite soft, about 5 minutes.: When you fold in the chopped bell pepper and drained chickpeas , you will see colors pop and the texture profile shift; the peppers will remain brighter when added now rather than earlier. The pot will make a softer bubbling sound and the steam will carry sweet pepper notes. As it simmers for about five minutes, the peppers should become tender yet still retain a slight bite, and the chickpeas will warm through and take on the surrounding flavors. Taste and adjust seasoning because salt needs to be balanced after these additions; the canned chickpeas can add residual saltiness if not rinsed. A typical mistake is letting this boil hard, which breaks the skins of the chickpeas and creates a cloudy, chalky texture, so keep it gentle.
Add the greens to the pot (and more stock if necessary) and cook for 1 minute, or until just-wilted. Check the soup for seasoning and serve it hot with cooked grains, drizzles of olive oil, lemon zest and chopped herbs.: Stirring in the chopped greens at the end adds a burst of color and fresh flavor; they will collapse quickly, changing from vivid and leafy to silky and folded into the broth in less than a minute. If the stew seems too thick, add a splash of extra vegetable stock so the greens have room to swirl and the final texture is brothy rather than gluey. After a quick wilt, sample the stew for salt and pepper and adjust, because flavors concentrate as it cools slightly. Serve hot over a scoop of cooked grain so the grain soaks up the savory tomato broth; finish each bowl with a drizzle of oil, a sprinkle of chopped parsley or cilantro , and a dusting of finely grated lemon zest to brighten the whole dish. The common error here is overcooking the greens which mutes their color and fresh bite, so add them last and remove from heat promptly.