Preheat the oven to 400°F. Spread the bread cubes on a baking sheet and toast in the oven for about 10-15 minutes, or until golden brown and crispy. Remove from the oven and let cool.
In a large bowl, combine the chopped tomatoes, cucumber, red onion, and torn basil leaves.
In a small bowl, whisk together the olive oil, red wine vinegar, salt, and black pepper.
Add the toasted bread cubes to the vegetable mixture. Pour the dressing over the salad and toss gently to combine. Let the salad sit for about 15-20 minutes to allow the bread to soak up the flavors.
Serve immediately or refrigerate for up to 1 hour before serving for a chilled option.