Place the baby potatoes in a pot and cover with water. Bring to a boil and cook until tender, about 15-20 minutes. Drain and let cool.

In a mixing bowl, whisk together balsamic vinegar, olive oil, Dijon mustard, minced garlic, salt, and black pepper until well combined.

In a large mixing bowl, combine the cooled potatoes, cherry tomatoes, cucumber, red onion, and basil. Pour the dressing over the salad and toss gently to combine.

Serve immediately or refrigerate for 30 minutes to allow flavors to meld before serving.