Rinse the quinoa thoroughly under cold water.
In a medium saucepan, combine the quinoa and water. Bring to a boil.
Cover, reduce the heat to low, and simmer for about 15 minutes, or until the water is absorbed and the quinoa is tender.
Remove from the heat and let it stand, covered, for 5 minutes.
Fluff the quinoa with a fork and transfer it to a large serving bowl to cool.
In a small bowl or mason jar, whisk together the olive oil, lemon juice, vinegar, honey, garlic, salt, and pepper until well combined.
Add the peaches, tomatoes, sweet corn, avocado, red onion, feta cheese, and basil to the cooled quinoa.
Pour the dressing over the salad and gently toss until everything is evenly coated. This Summer Quinoa Salad is best served immediately or chilled before serving.