Bring a medium pan of salted water to the boil. Add quinoa and cook until softened, about 15 minutes. Drain and reserve.
While the quinoa is cooking, make the vinaigrette. Whisk together the orange juice, ginger, garlic and soy sauce. Continue whisking and drizzle in the sesame oil.
Place the mustard greens, scallions, carrots and reserved quinoa in a large bowl. Toss with the vinaigrette and serve!