Spray a 9x13-inch dish; spread bread evenly.
Scatter tomatoes, mozzarella, basil, and garlic over bread.
Whisk eggs, half-and-half, salt, and pepper smooth in a large bowl.
Pour evenly over filling; press gently to soak. Cover and refrigerate at least 2 hours or overnight.
Heat oven to 350°F; bake uncovered 40-45 minutes until puffed and golden.
Cool 5 minutes; drizzle with glaze and garnish with basil. To freeze, cool completely, portion, wrap in plastic and foil, and freeze up to 2 months. Microwave portions 2-3 minutes or reheat at 350°F for 15-20 minutes.