Pound each chicken breast to an even thickness of about 1 inch to ensure uniform cooking. This helps the chicken cook evenly and stay tender.
Heat a skillet over medium-high heat until it’s hot and shimmering. Add a splash of olive oil and let it coat the pan evenly. Place the chicken breasts in the skillet and sear for about 6-7 minutes per side, or until golden brown and the internal temperature reaches 75°C (165°F).
Once cooked, transfer the chicken to a plate and let it rest for 5 minutes. Resting keeps the juices locked in, resulting in tender slices later.
Meanwhile, in a small bowl, whisk together lemon juice, Dijon mustard, honey, and olive oil until the dressing is smooth and slightly emulsified. Season with salt and pepper to your taste. This bright dressing will bring all the flavors together.
Slice the rested chicken thinly against the grain, revealing a juicy interior and golden edges.
In a large mixing bowl, combine the mixed greens, halved cherry tomatoes, and thinly sliced red onion. Toss gently to distribute evenly.
Add the sliced chicken on top of the greens and vegetables. Drizzle the prepared dressing over the salad.
Toss everything gently to coat the ingredients with the dressing, making sure the greens stay crisp and the chicken remains juicy.
Garnish with optional chopped herbs or a sprinkle of crumbled feta cheese for extra flavor and presentation.
Serve immediately for the best crispness and juiciness, and enjoy this fresh, satisfying chicken salad.