Place a large pot of water on to boil for pasta. Salt water and add bucatini and cook to al dente.
While water comes to boil and pasta cooks, make the sauce. Heat a large, deep nonstick skillet over medium high heat. Add 1 tablespoon extra-virgin olive oil, 1 turn of the pan. Add sausage to the skillet and break up the sausage into small bits. Brown sausage all over then transfer to a paper towel lined plate. Return pan to heat and add 2 tablespoons extra-virgin olive oil, 2 turns of the pan, the garlic, fennel, onions and peppers. Season the vegetables with salt and pepper. Cook, turning frequently, 7 to 8 minutes until tender but do not allow the fennel and onions to brown ¿ reduce heat a bit if they begin to. Add the wine or stock next and reduce 2 minutes. Stir in the tomatoes and the sausage. Reduce heat to a simmer and cook until pasta is done.
Drain the pasta very well and add to the sauce. Sprinkle the pasta with 1/2 cup cheese, a couple of handfuls, then toss pasta with thick sauce to combine. Transfer pasta to a large shallow platter and cover with the pasta with basil leaves. Serve with extra cheese and pass crusty bread at the table to mop up the plates.