Heat the olive oil in a large pot or Dutch oven over medium heat. Add the chopped onion and cook until softened, about 5 minutes. Add the minced garlic and grated ginger, and cook for another minute until fragrant.
Stir in the turmeric powder, cumin powder, and red pepper flakes (if using). Cook for 30 seconds, stirring constantly, to bloom the spices and release their flavor.
Pour in the vegetable broth and add the diced sweet potato, cauliflower florets, green beans, diced tomatoes (undrained), and chickpeas. Stir well to combine.
Bring the stew to a boil, then reduce the heat to low, cover, and simmer for 20-25 minutes, or until the sweet potato and cauliflower are tender.
Season the stew with salt and pepper to taste. Stir in the chopped cilantro. Serve hot and enjoy!
