Preheat oven to 375°F (190°C). Bring a large pot of water to a rolling boil; add 1 tablespoon salt.

Cook ziti until just al dente according to package directions (about 7-8 minutes). It will continue cooking in the oven, so drain it 1 minute before the package says. Drain and rinse briefly with cool water to stop cooking.

In a medium bowl, combine ricotta, egg, Parmesan, basil, garlic powder, salt, and pepper. Mix until smooth.

Spread 1 cup of marinara sauce in the bottom of a 9x13-inch baking dish. Add half the ziti, then dollop all of the ricotta mixture over it, spreading gently. Sprinkle with 1 1/2 cups mozzarella, then spread 1 cup marinara on top. Add remaining ziti, then remaining 1 cup marinara. Top with remaining 1 1/2 cups mozzarella and 1/4 cup Parmesan.

Cover tightly with foil and bake for 20 minutes. Remove foil and bake another 10–15 minutes until bubbly and golden on top and the centre reaches an internal temperature of 160°F (71°C). Let rest 10 minutes before serving.

Sprinkle with fresh basil and serve hot, scooping all the way to the bottom for perfect layers.