Chop the onions, set aside. Finely chop the garlic, set aside. Peel and cube the sweet potato, chop the broccoli stalk into cubes, set both aside. Divide the rest of the broccoli into small florets. Drain and wash the chickpeas. Keep the broccoli florets and the chickpeas separated from the rest of the vegetables.
Heat the oil in a soup pot. Cook the onions until golden, add the garlic and the spices, and let cook for another minute or so until fragrant.
Add the sweet potato and the broccoli stalk and stir to coat with the spices. Let cook for about 1-2 minutes taking care not to burn the garlic and the spices.
Add the vegetable broth and bring everything to a boil. Let cook for about 5 minutes. Add the broccoli florets and the chickpeas. Let cook until the sweet potato is soft (it won't take too long).
Add soy sauce, vinegar, sriracha, stir well and adjust the taste with salt and pepper.