In a large saucepan, bring water and tomato juice to a boil. Add quinoa. Reduce heat; cover and simmer until liquid is absorbed, 18-22 minutes. Remove from the heat; fluff with a fork., In a large skillet, saute onion in oil until tender. Add garlic and pepper flakes; cook 1 minute longer. Stir in kale and cook until wilted, 3-4 minutes., Stir in pine nuts and currants; cook until kale is tender, about 2 minutes. Stir in the vinegar, lemon juice, zest, salt and pepper; cook 1-2 minutes longer. Remove from the heat and stir in quinoa. Serve at room temperature.