Place raisins in a small bowl and cover with warm water; let soak for 10 minutes. Drain.

Crush saffron and salt together in a mortar and pestle until a coarse powder forms. (Alternatively, place saffron and salt on a cutting board and use the flat side of a chef's knife to grind into a coarse powder.) Combine with ginger, turmeric, allspice, nutmeg, cinnamon and pepper in a small bowl.

Heat 2 tablespoons olive oil and butter in a Dutch oven over medium heat. Add the spice mixture and cook, stirring, until the mixture starts to foam. Add onions, sugar and the plumped raisins. Cook, stirring occasionally, until the onions turn light brown, 20 to 25 minutes. Add 1 cup broth and nestle fish into the onion mixture. Cover and cook until the fish is flaky, 8 to 10 minutes. Remove from the heat and season with pepper. Cover and set aside.

Meanwhile, heat canola oil in a small skillet over medium-high heat. Add almonds and cook, stirring, until just beginning to turn golden, about 1 minute. Drain on paper towels.

Bring the remaining 1 1/3 cups broth and the remaining 2 tablespoons olive oil to a boil in a small saucepan. Add couscous in a stream. Stir once. Cover, remove from the heat and let stand for 5 minutes. Fluff with a fork.

To serve, mound the couscous on a shallow platter. Top with the fish and onion t'faya and sprinkle the almonds on top.

Ingredient note: The dried stigma from Crocus sativus, saffron adds flavor and golden color to a variety of Middle Eastern, African and European foods. Find it in the spice section of supermarkets, gourmet shops and at tienda.com. It will keep in an airtight container for several years.