Wash quinoa in several changes of cold water in a bowl, rubbing grains between your palms, then drain well. Bring quinoa and 5 cups water to a boil in a large saucepan, then reduce heat and simmer, uncovered, until grains are translucent, 13 to 15 minutes. Drain well in a sieve.
Preheat oven to 350°F.
Whisk together eggs, milk, vanilla, 3/4 cup sugar, and salt in a large bowl until just combined. Stir in quinoa, almonds, and currants. Pour into a buttered 9-inch square metal baking dish.
Stir together cinnamon and a bit more sugar and sprinkle over top of pudding. Bake in middle of oven until a knife inserted in center comes out clean, about 40 minutes. Serve warm or at room temperature.
For a lactose-free pudding, use Organic Valley Lactose-Free Milk.