Boil 2 cups of water in large saucepan. When boiling, add quinoa and then return to a boil. Lower heat and cover, cooking for about 15-20 minutes.
In a large saute pan, heat 1T olive oil. Add pepper, onion, corn and celery and cook until soft, about 3 minutes.
To prepare dressing, combine vinegar, agave nectar, lemon juice and mustard in a bowl. Slowly incorporate the olive oil in a steady stream, whisking until well mixed. Add salt to taste.
When quinoa is done and cooled, add cooked vegetables and cucumber. (You can do this in the same pot you cooked the quinoa). Mix well and add dressing, followed by fresh parsley.
Recipe by Prepgreen at https://www.prepgreen.com/colorful-quinoa-salad-with-an-array-of-vegetables/