When the water comes to a boil, add to a saucepan: the sweet potatoes, potatoes and spinach. Cook for 15 until soft. In the other saucepan, add: 1/3 of the salt and the brussels sprouts. Cook for 4 min. Meanwhile, in a large bowl, mix well: 1/3 of the salt, cumin powder, cayenne pepper, cilantro (chop) and fenugreek leaves. Set aside.