Caprese Salad with Grilled Flank Steak

Ingredients (10)

• + 2 tomatoes, diced add to pantry
• + 1 (4 ounce) ball fresh mozzarella, cut into 1-inch cubes add to pantry
• + ¼ cup coarsely chopped fresh basil add to pantry
• ✓ 1 clove garlic, minced, or more to taste
• + 1 tablespoon olive oil add to pantry
• + 1 pound flank steak add to pantry
• ✓ salt and ground black pepper to taste
• + salt and ground black pepper to taste add to pantry
• + 1 (6.5 ounce) bag butter lettuce mix add to pantry
• ✓ 2 tablespoons balsamic vinegar, or to taste