Bring two cups of water to a boil in a saucepan, and season with salt. Add the quinoa and reduce to a simmer. Cover and cook until the water is completely absorbed, about 10-12 minutes. The quinoa is cooked when the spiral germ becomes visible around the grains.
Meanwhile, prepare the Dijon vinaigrette. In a bowl, whisk oil, vinegar, Dijon, honey, and garlic powder until thoroughly combined. Season thoroughly with salt and pepper and whisk again.
In a large bowl, add the cooked quinoa, avocado, corn, chopped chives, and the Dijon vinaigrette. Stir until well combined. Carefully fold in tomatoes.
Salad tastes best served chilled, and leftovers may be stored in the fridge in an airtight container.