1red onionthinly sliced and separated into individual rings (cut in half if really large)
Salt and Pepper to taste
Prepare the dressing: In a small bowl (or jar), combine all the dressing ingredients and whisk or shake together well. Set aside.
Arrange sliced tomatoes in a single layer, overlapping just slightly, in a shallow dish or deep plate. Season tomatoes with salt and pepper. Evenly scatted chopped basil overtop of tomatoes.Spread red onion over tomatoes, then basil, then sprinkle the crumbled feta cheese over the top.
Drizzle with the dressing. Let stand at room temperature for at least 15 minutes before serving.
If you are making well ahead you'll want to refrigerate it. Just be sure to remove from the fridge an hour before serving to bring it to room temperature.