In a microwave-safe bowl, add onions and garlic. Cook for 2-3 minutes to soften. In a large bowl, combine cooked quinoa, cooked onions, and garlic, drained black beans, enchilada sauce, green chiles, corn, ½ cup yogurt or sour cream, ½ cup light shredded cheese, chili powder, and cumin. Season with salt and pepper, to taste. Mix well.