01 - Rinse quinoa thoroughly under cold running water until water runs clear. Combine quinoa, water, and salt in a medium saucepan. Bring to a rolling boil over high heat, then reduce heat to low, cover tightly, and simmer for 15 minutes until all water is absorbed. Remove from heat, fluff gently with a fork, and let cool completely.
02 - Fill a large pot with salted water and bring to a vigorous boil. Add asparagus, sugar snap peas, and peas. Blanch for exactly 2 minutes until vegetables are bright green and just tender-crisp. Drain immediately and transfer to an ice bath to halt cooking. Drain well and pat dry.
03 - In a large mixing bowl, add cooled quinoa, blanched vegetables, radishes, cherry tomatoes, red onion, parsley, mint, and chives. Toss gently to distribute ingredients evenly.
04 - Whisk together olive oil, lemon juice, Dijon mustard, honey, minced garlic, salt, and pepper in a small bowl or jar. Continue whisking vigorously until mixture is fully emulsified and slightly thickened.
05 - Pour vinaigrette over salad mixture and toss thoroughly to coat all ingredients. Taste and adjust salt and pepper as needed. For optimal flavor, let salad marinate for 10-15 minutes before serving.
06 - Transfer salad to a serving platter or shallow bowl. Top with crumbled feta cheese if desired. Serve immediately while vegetables retain their crunch, or refrigerate for up to 2 hours before serving.