Preheat oven to 400 degrees F.
Heat a 12-inch oven-safe skillet over medium high heat. Add the ground beef and brown, crumbling, until no longer pink, about 6 minutes. Drain off any excess grease.
Stir in the garlic and cook for 30 seconds, stirring.
Reserve ¾ cup of the marinara sauce and add the rest of the sauce to the skillet. Fill the empty marinara sauce jar with water, almost to the top, and add the water to the skillet (this will be about 3 cups of water, the jar makes it easy to measure).
Add the Italian seasoning and ziti to the skillet. Stir to combine.
Cover and cook at a simmer, stirring often, until the pasta is just tender, about 15 to 18 minutes. There may be a little bit of liquid left in the skillet and this will be absorbed later. Remove from the heat.
Stir in the ricotta and ¼ cup of the Parmesan. Spoon the reserved ¾ cup marinara sauce on top.
Sprinkle the mozzarella and remaining ¼ cup Parmesan on top. Place the skillet, uncovered, in the oven. Bake until the cheese has melted and browned and the sauce is bubbling, 10 to 15 minutes.