Preheat oven to 350°. In a small bowl, mix cream cheese and 1 teaspoon basil until blended; spread onto 6 bread slices. Top with mozzarella cheese and remaining bread. Spread outsides of sandwiches with butter. Arrange in a greased 13x9-in. baking dish., In a small saucepan, combine tomato paste, garlic, salt, pepper and remaining basil; cook and stir over medium heat 1 minute. Gradually whisk in milk; bring to a boil. Reduce heat; simmer, uncovered, 4-5 minutes or until thickened, stirring frequently. Remove from heat., Whisk eggs in a large bowl; gradually whisk in a third of the milk mixture. Stir in remaining milk mixture; pour over sandwiches. Sprinkle with Italian cheese blend., Bake, uncovered, 25-30 minutes or until golden brown and cheese is melted. Let stand 10 minutes before serving.