Toss the bread with your vegetables. In a large bowl, add 4 cups cubed baguette bread, 1 seeded and sliced English cucumber, 1 ½ pounds quartered cherry tomatoes, ¼ thinly sliced red onion, 1 ½ sliced roasted red bell peppers, ⅓ cup capers, and ½ cup pitted Kalamata olives, and toss lightly.
Make the dressing then mix with the other salad ingredients. In a jar with a fitted lid, add ⅓ cup olive oil, 2 tablespoons red wine vinegar, 1 ½ teaspoons Italian seasoning, 1 pressed garlic clove, ½ teaspoon kosher salt, and ½ teaspoon freshly ground black pepper. Shake well, taste, and season with more salt and pepper if needed. Pour over the salad and toss to coat.
Refrigerate for the flavors to meld, then serve. Refrigerate for 1 hour. Toss the salad to freshen the ingredients, drizzle with a bit more olive oil, then top with ½ cup slivered or torn fresh basil leaves and ⅓ cup crumbled feta cheese, and serve.