Bring a large pot of water to a boil for the pasta. Salt the water and add the pasta. Cook until 1 minute shy of the package directions. Reserve 1 cup of the cooking water, then drain.
Meanwhile, in a large skillet or saucepot, heat the olive oil, two turns of the pan, over medium-high. Add the pancetta and cook, stirring often, until the fat renders, about 2 minutes. Add the onion and garlic and cook, stirring often, until softened, about 3 minutes. Add the sausage and beef; season with salt, pepper, the fennel seeds, and sage. Cook, stirring occasionally and breaking the meat up with a wooden spoon, until browned and cooked through, 5 to 7 minutes. Add the wine and cook until absorbed, just a minute or two. Add the tomatoes and stock and simmer, stirring occasionally, until the sauce thickens, 10 to 15 minutes.
Toss the pasta with the sauce, cooking water, and a fat handful of cheese. Drizzle with EVOO to taste. Serve and pass more cheese at the table.