Bring a large pot of lightly salted water to a boil. Add manicotti and cook for 8 to 10 minutes or until al dente; drain.
Preheat oven to 350 degrees F (175 degrees C). Lightly grease a 9x13 inch baking dish.
In a bowl, mix 3 cups mozzarella cheese, ricotta cheese, 1/2 cup Parmesan cheese, garlic, egg, and basil. Stuff cooked manicotti with the mixture.
Spread about 2 cups pasta sauce over the bottom of the prepared baking dish. Arrange stuffed manicotti in the dish, and cover with remaining sauce. Sprinkle with remaining mozzarella cheese.
Bake 15 minutes in the preheated oven. Sprinkle with remaining Parmesan, and continue baking 10 minutes, until mozzarella is melted and bubbly.
Preheat the oven on broiler setting.
In a large bowl, combine the roma tomatoes, sun-dried tomatoes, garlic, olive oil, vinegar, basil, salt, and pepper. Allow the mixture to sit for 10 minutes.
Cut the baguette into 3/4-inch slices. On a baking sheet, arrange the baguette slices in a single layer. Broil for 1 to 2 minutes, until slightly brown.
Divide the tomato mixture evenly over the baguette slices. Top the slices with mozzarella cheese.
Broil for 5 minutes, or until the cheese is melted.