In a medium bowl, whisk together the white balsamic vinegar, lemon zest, and Dijon mustard. Add a pinch of kosher salt to taste and slowly drizzle in the olive oil while continuously whisking until smooth.

In a large mixing bowl, combine the sliced yellow peaches, halved Persian cucumbers, fresh blueberries, thinly sliced shallot, and torn basil. Gently stir to distribute the ingredients.

Carefully crumble the feta cheese over the mixture and gently fold it in.

Drizzle the prepared vinaigrette over the salad and toss gently to coat all ingredients.

Allow the salad to sit at room temperature for about 10 minutes before serving.