Bring a large pot of salted water to a boil and cook the ziti until just shy of al dente. Drain.

In a bowl, stir together ricotta, 1 cup/100 grams mozzarella, oregano, basil, parsley, garlic, and heavy cream until smooth. Season with salt and pepper.

In a large skillet over medium-high heat, cook the ground beef, breaking it up, until browned. Add bell pepper, onion, and garlic and cook until softened. Stir in tomato paste, crushed tomatoes, and diced tomatoes. Season with salt, pepper, and Italian seasoning. Simmer until slightly thickened, 10 to 15 minutes. Taste and adjust seasoning.

Add the cooked pasta to the ricotta mixture and stir to coat evenly. Taste and adjust seasoning.

Spread a thin layer of meat sauce in a baking dish. Add half the pasta, then half the remaining sauce. Repeat, finishing with sauce. Top with remaining mozzarella and Parmesan.

Bake until bubbling, about 20 minutes. Broil on low until lightly browned, 3 to 5 minutes. Let rest briefly, then top with parsley and serve.