Add the spinach and jalapeño (and chickpeas if you want to make this a more substantial main-course-type dish) to the onions and stir to combine. Pour in 1 cup of hot water and mix well. Slowly add the rice flour, stirring constantly to prevent any lumps from forming, and bring to a boil. Reduce the heat to medium-low (a very low simmer) and cook for 20 minutes. Add salt to taste, and transfer to a serving dish.