Cooking Instructions:
Begin by marinating the chicken breasts. In a bowl, combine olive oil, lemon juice, Dijon mustard, salt, and pepper. Add the chicken breasts, ensuring they're well coated. Allow them to marinate for at least 30 minutes in the refrigerator to enhance the flavor.
Preheat your grill or grill pan over medium-high heat. Once hot, remove the chicken from the marinade and place it on the grill. Cook for about 6-7 minutes on each side, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C). Remove from the grill and let it rest for 5 minutes before slicing.
While the chicken is resting, prepare the salad. In a large bowl, combine the mixed greens, cherry tomatoes, cucumber, and red onion. Toss the ingredients together gently.
Slice the grilled chicken into strips and add it on top of the salad. Sprinkle the feta cheese over the top and garnish with fresh herbs.
For the dressing, you can use the leftover marinade or make a fresh batch by whisking together olive oil, lemon juice, salt, and pepper. Drizzle the dressing over the salad just before serving.