Render the pancetta chunks in a large pan over medium heat until brown, about 10 minutes. Add the onions and cook over medium-low heat until lightly caramelized, about 15 minutes. Add the garlic and red pepper flakes to the pan and stir until fragrant. Add the tomatoes, season with salt and bring to a simmer. Cook the sauce, stirring occasionally, until most of the excess liquid has evaporated, about 1 hour.
Preheat a convection oven to 375 degrees F.
Mix the sauce with the pasta in a large bowl.
Put half the sauced pasta in a deep, half hotel pan. Top with the chunked mozzarella and the remaining sauced pasta.
Mix the panko, Parmesan, oregano and oil in a medium bowl. Sprinkle over the top of the pasta. Bake until bubbly and browned on top (cover with foil if the top browns too much), about 30 minutes.
Copyright 2016 Television Food Network, G.P. All rights reserved.