Make the Lettuce: Pile the lettuce in a large shallow serving bowl. Arrange the tomatoes, pepper, onion, feta, chicken, and cucumber on top of the lettuce.
Make the Dressing: In a small container combine the olive oil, lemon juice, rice vinegar, Dijon and thyme. Season with salt and pepper, and shake to combine. Pour the dressing over the salad, toss and serve.
Notes
Obviously you can use different colored bell peppers, add halved and sliced radishes, or cubed small zucchini or whatever summer vegetables are inspiring you or begging to be put to good use. And of course use any color onion you have around – but the red or purple ones have some curb appeal.