In a large bowl, combine the sliced strawberries, crumbled feta cheese, thinly sliced red onion, and chopped basil leaves.

In a small bowl, whisk together the balsamic vinegar, olive oil, salt, and pepper to create the dressing.

Drizzle the dressing over the salad mixture and gently toss to combine, ensuring that the strawberries and feta are well coated.

Cover the salad with plastic wrap and refrigerate for at least 30 minutes to allow the flavors to meld together.

Before serving, give the salad a gentle toss again and serve it over a bed of mixed salad greens if desired.