To cook quinoa, bring water to boiling in a medium saucepan. Add the quinoa and cook; reduce heat. Cover and cook for 12 minutes or until tender. Drain well. Spread out on a paper-towel-lined baking sheet. Pat dry and let cool for 10 minutes.
Meanwhile, for dressing, in a small bowl whisk together 3 tablespoons olive oil, vinegar, and salt; set aside.
Heat remaining 1 tablespoon olive oil in a large nonstick saute pan over medium-high heat. Add the quinoa. Cook and stir for 5 minutes. Spread quinoa evenly in pan and continue to cook for 10 minutes more or until quinoa is lightly toasted, stirring occasionally and reducing heat to medium, if necessary.
Transfer the quinoa to a medium bowl. Add the cranberries, pistachios, celery, and green onions. Add the dressing and toss to coat. Season to taste with pepper and additional salt, if desired.