Rinse the quinoa, and place in a saucepan with 1 cup of water and a few pinches of salt.  Bring to a boil, reduce heat, and cover, cooking for 15-20 minutes, until the quinoa is tender, and has absorbed the liquid.

Cut the onions cross-wise into thick slices.  Cut the zucchini length-wise into thin strips.  Remove the husks from the corn, and cover each in aluminum foil.

Preheat your bbq to medium-high.  Brush the veggies with olive oil, and salt liberally.  Place on the hot grill, and cook, turning them often, until the zucchini are soft, and the onions have become slightly charred (10-15 min).  Continue cooking the corn for another 15-20 minutes, turning it occasionally for even cooking.  

Let the corn cool a bit, and cut off the kernels.  You should get about 1-2 cups. Separate the onion rings.  Mix all veggies with the cooked quinoa.

Mix the juice of the lemons, with the olive oil, and pressed garlic.  Pour the dressing over the quinoa, and grilled veggies.  Top with the fresh mint, and toasted pepitas.