Soak the quinoa for 10 to 15 minutes in cool water, then rinse in a strainer until the water runs clear. Drain well.
Bring 3/4 water to a boil, add the quinoa, stir well.
Reduce to a simmer, cover, and cook for 20 to 25 minutes, or until the water is completely absorbed.
Rest 5 minutes and fluff with a fork. Set aside to cool.
Cook the corn kernels for 2 to 3 minutes in boiling water and set aside to cool, or leave them raw.
Zest the lime, and mince the zest finely. Juice the lime and combine the juice with the zest.
Combine the cooled quinoa, corn, lime juice and zest, onion, bell pepper, cilantro, and beans with the vinaigrette, mixing gently (best done with your hands).
Season to taste and serve over salad greens with a sprinkle of pumpkin seeds.