Preparation

• Position a rack in the center of the oven and heat to 425°F.
• On a rimmed baking sheet, toss the bread cubes with 3 Tbs. of the oil, the garlic, 1/2 tsp. salt, and 1/4 tsp. pepper, spread in a single layer, and toast, tossing halfway through, until light golden brown, 9 to 10 minutes.
• Meanwhile, in a small bowl whisk the remaining 2 Tbs. oil, the balsamic vinegar, lemon juice, 1/4 tsp. salt, and 1/4 tsp. pepper.
• In a medium bowl, combine the bread cubes, green beans, tomatoes, mozzarella, and vinaigrette. Let the salad sit, tossing occasionally, until the bread begins to soften, about 20 minutes. Season to taste with salt and pepper, and serve.