1. To prepare salad, heat 1 teaspoon oil in a large nonstick skillet over medium-high heat. Add white onion to pan; sauté 2 minutes. Add quinoa to pan; sauté 5 minutes. Add 2 cups water and 1/2 teaspoon salt to pan; bring to a boil. Cover, reduce heat, and simmer 15 minutes. Remove from heat; let stand 15 minutes or until water is absorbed. Transfer quinoa mixture to a large bowl. Add orange and next 5 ingredients (through jalapeño); toss gently to combine.
2. To prepare dressing, combine juice and next 4 ingredients (through garlic) in a small bowl, stirring with a whisk. Pour dressing over salad; toss gently to coat. Sprinkle with chopped mint. Garnish with mint sprigs, if desired. Serve at room temperature.