1⁄4 cup balsamic vinegar
4 tsp. honey
1 tsp. kosher salt
1⁄4 tsp. freshly ground black pepper
1/2 small red onion, cut into thin slices
4-lb. piece of watermelon, rind and seeds removed
4 large ripe tomatoes (about 1 1⁄2 lbs.), stemmed and cored
1⁄4 cup extra-virgin olive oil
1 loosely packed cup roughly torn basil leaves
Kosher salt and freshly ground black pepper, to taste
6 ounces crumbled feta cheese (optional)
Whisk vinegar, honey, salt, and pepper together in a small bowl. Add onions and toss to combine. Set aside.
Quarter and thinly slice onion. Stir onions into the vinegar mixture. Cover with plastic wrap and let stand at room temperature for 30 minutes.
Cut watermelon into 2-inch pieces and place in a large bowl. Cut tomatoes in half, vertically, and then cut into 2-inch thick pieces. Combine the tomatoes and watermelon in a large bowl. Add the reserved onion mixture-onions and marinade- and olive oil and basil. Gently toss salad. Add salt and pepper, as desired.
Makes 4-6 servings.