Prep the Ingredients. Start by preparing the watermelon, cucumber, red onion, and mint. Dice the watermelon into bite-sized cubes, thinly slice or dice the cucumber, and finely chop the mint leaves. If using red onion, thinly slice it and soak it in cold water for a few minutes to mellow out the flavor.
Assemble the Salad. In a large serving bowl, combine the diced watermelon, sliced cucumber, crumbled feta cheese, and soaked red onion (if using). Gently toss the ingredients together until evenly distributed.
Season and Garnish. Season the salad with salt and pepper to taste. Sprinkle the chopped mint leaves over the salad for a fresh and aromatic finish.
Drizzle with Balsamic Glaze. Just before serving, drizzle the salad with balsamic glaze for a sweet and tangy flavor contrast. You can adjust the amount of glaze according to your preference.
Serve and Enjoy. Serve the Watermelon Feta Salad immediately as a refreshing side dish or appetizer. Garnish with additional mint leaves for an extra pop of color and freshness.