In a large bowl, combine the Ricotta Cheese (1 cup), Crème Fraîche (1 cup), Egg (1), and 1/2 cup of the Pecorino Romano Cheese (1/2 cup). Season with Kosher Salt and Freshly Ground Black Pepper (to taste) and set aside.
Heat the Olive Oil (2 tablespoon) in a 12-inch skillet over medium heat. Add the Onion (1) and cook until softened, about 4 minutes. Add the Garlic (2 clove), Crushed Red Pepper Flakes (1 teaspoon), and Fresh Oregano (1 tablespoon), and cook for 2 minutes more.
Add the Spicy Italian Sausage (1 pound) and cook until browned, breaking up the meat with the back of a wooden spoon (or some clean scissors). Add the San Marzano Tomatoes (1 can) and the San Marzano Tomatoes (1 can) and bring to a simmer. Season to taste, and cook until the sauce has thickened, about 20 minutes.
Preheat the oven to 400 degrees F (200 degrees C).
Bring a large pot of water to a boil. Add 2 tablespoons of the salt and return to a rolling boil. Add the Ziti Pasta (1 pound), and cook for 4 minutes short of al dente according to package directions. Drain, reserving 1/2 cup pasta water.
Add the Chard (5 ounce) to the sauce with 1/2 cup pasta water, stirring until it wilts. Remove from the heat. Stir half of the sauce into the ricotta mixture. Add the pasta and toss together to coat.
Pour the pasta into a 9x13-inch baking dish. Top with the remaining sauce. Sprinkle the Mozzarella Cheese (0.75 pound) and remaining Pecorino Romano Cheese (1/2 cup) over the top and bake until the cheese starts bubbling, about 20 minutes.
Set the oven to broil and broil until the ricotta cheese and pasta are browned in spots, about 5 minutes more. Keep a close watch the entire time—a minute or two might be all it needs.
Remove from the oven and let rest for 5 minutes before serving.