Bring a large pot of salted water to a boil. Add the manicotti tubes and cook until al dente, about 6–8 minutes; drain in a colander, rinse under cool water, and toss with 2 teaspoons olive oil to prevent sticking.
Preheat the oven to 400°F (200°C).
In a large bowl, combine the drained ricotta, 1 cup mozzarella, grated Parmesan, Italian seasoning, chopped parsley, chopped basil, salt, and pepper; mix until well blended.
Fill each manicotti tube with the cheese mixture using a piping bag or a spoon.
Spread 1 1/4 cups marinara sauce in the bottom of a 9×13-inch baking dish. Arrange the filled manicotti over the sauce, then pour the remaining marinara evenly over the shells. Sprinkle additional mozzarella on top as desired.
Cover the dish with foil and bake for 30 minutes. Remove the foil and bake uncovered for 10 more minutes, until the cheese is bubbly and lightly browned.
Let the baked manicotti rest for a few minutes, then garnish with additional basil and serve.