Bring a large pot of salted water to a boil over high heat. Add the pasta and partially cook until tender but still very firm to the bite, stirring occasionally, about 4 to 5 minutes. Drain pasta.
Meanwhile, in a large heavy frying pan, heat the olive oil over medium-high heat. Add the onions and the garlic and cook until the onions are soft and starting to brown, about 3 minutes. Add the ground turkey, 1/2 teaspoon salt, and 1/4 teaspoon black pepper and continue to cook, stirring occasionally, until the meat is slightly golden and cooked through. Add the artichoke hearts and stir to combine. Remove from heat and let cool.
In a large bowl combine the cooled turkey mixture with the ricotta cheese, Parmesan cheese, eggs, basil, parsley, and the remaining salt and pepper. Stir to combine.
To stuff the shells, cover the bottom of a 9 by 13 by 2-inch baking dish with 1 cup of Arrabbiata sauce. Take a shell in the palm of your hand and stuff it with a large spoonful of turkey mixture, about 2 tablespoons. Place the stuffed shell in the baking dish. Continue filling the shells until the baking dish is full, about 24 shells. Drizzle the remaining Arrabbiata Sauce over the shells, top with the grated mozzarella. If freezing, cover tightly with plastic wrap and place in the freezer for 1 day and up to 1 month.
To bake, preheat the oven to 205°C. Bake until the shells are warmed through and the cheese is beginning to brown, about 60 minutes (20 minutes if shells are unfrozen.)
Heat the olive oil in a large soup pot over medium heat. Add the pancetta and saute until golden brown, about 5 minutes. Add the garlic and saute until tender, about 1 minute. Add the marinara sauce and red pepper flakes and bring to a simmer. Remove from heat and let cool until ready to use.