Toast the pine nuts in small skillet over medium-low heat. Set aside to cool.
Put the raisins in a small bowl and cover them with boiling water. Let them soak for about 10 minutes or until plump and soft. Drain the water.
Rinse the spinach leaves. Put them in a very large pan with only the water that clings to the leaves. Cook the spinach, turning frequently, until the leaves turn bright green and are wilted. Drain the spinach, cool, then roughly chop.
Heat the oil in a skillet over medium heat. Add the onions and sauté them until they are soft. Add the spinach, raisins and pine nuts and cook together until heated. Season with salt and pepper and serve hot, warm, or at room temperature.