In a saucepan, combine the cumin and saffron over medium heat. Toast, stirring, until fragrant and slightly darkened in color, about 2 minutes. Add the rice and stock and season with 1/2 teaspoon salt, if desired. Raise the heat to high, cover, and bring to a simmer. Reduce the heat to low and cook for 15 minutes. Remove from the heat and let stand, covered, for 10 minutes. The rice will have absorbed the liquid and be tender.
Meanwhile, in a sauté pan, heat the olive oil over medium heat. Add the onion, garlic, and ginger and cook, stirring, until softened, about 10 minutes. Add the curry powder and cook, stirring, until aromatic, 3-4 minutes. Add the cream, 1/4 cup (2 fl oz/60 ml) water, the chickpeas, and 1/2 teaspoon salt and stir to combine. Taste and adjust the seasoning. Add the spinach and sauté until wilted, 2-3 minutes.
Spoon the rice onto plates and top with the curried chickpeas and spinach. Garnish with the lemon juice and with the yogurt, if desired, and serve right away.
Recipe reprinted with permission from Classic Recipes for Modern People by Max and Eli Sussman, Weldon Owen 2015.