Add the spinach or field greens to a large serving bowl.
Top with sliced strawberries, blueberries, mandarin oranges, avocado, sliced almonds, and cooked chicken.
Gently toss the salad ingredients until evenly distributed.
In a small bowl or jar, whisk together the Greek yogurt, apple cider vinegar, olive oil, honey, salt, mustard, and poppy seeds until smooth.
Pour the desired amount of dressing over the Strawberry Chicken Salad.
Toss gently to coat all ingredients evenly.
Serve immediately and enjoy.