5 large Yukon Gold potatoes
1 large cucumber, chopped
5 stalks celery, chopped
1 large red onion, chopped
3/4 cup green olives with pimento, chopped
1/4 cup olive oil
1/2 cup red wine vinegar
1/4 teaspoon garlic powder
salt and ground black pepper to taste
Place potatoes in a large saucepan, cover with water, and bring to a boil over high heat. Reduce the heat to medium-low, and simmer until the potatoes are tender, about 15 minutes. Drain and cool, then cut into 1-inch cubes.
Combine the potatoes, cucumber, celery, onion, and olives in a large bowl.
Whisk together the olive oil, red wine vinegar, and garlic powder in a small bowl. Pour the dressing over the potatoes and vegetables; mix well. Season with salt and pepper, then chill. Stir the potato salad again before serving.