01 - In a medium saucepan, combine quinoa, water, and sea salt. Bring to a boil, then reduce heat to low, cover, and simmer for 15 minutes. Remove from heat, keep covered for 5 minutes, then fluff with a fork. Allow quinoa to cool completely.
02 - Preheat a grill or grill pan over medium-high heat. Lightly brush peach halves with olive oil.
03 - Place peach halves cut-side down on the grill. Grill for 3 to 4 minutes until distinct grill marks form and peaches are slightly softened. Remove and let cool, then slice each half into wedges.
04 - In a small bowl, whisk together extra-virgin olive oil, honey, lemon zest, lemon juice, white wine vinegar, Dijon mustard, salt, and freshly ground black pepper until fully emulsified.
05 - In a large mixing bowl, combine cooled quinoa, cherry tomatoes, red onion, arugula or mixed greens, and basil. Gently fold in grilled peach wedges and crumbled feta cheese if using.
06 - Drizzle the salad with vinaigrette and gently toss until coated. Taste and adjust seasoning as needed. Serve immediately or refrigerate for up to 2 hours for enhanced flavors.