01 -
Fill a big pot with water, salt it generously, and bring it up to a rolling boil.
02 -
Take a 3-quart sauté pan and heat it up over medium-high with enough olive oil to coat the pan. Toss in the sausage, break it into chunks using a wooden spoon, sprinkle with salt, and cook until browned, roughly 5 minutes. Scoop it out with a slotted spoon and set aside.
03 -
Turn the heat down to medium. Toss some butter in the pan, and when it's completely melted, add the onion and fennel. Stir often while cooking for about 8 minutes so they become golden and soft. Sprinkle on some salt to season them.
04 -
Toss the pasta in the pot of boiling water. Stir right away and follow the time on the package to cook it 'al dente.'
05 -
Mix in the garlic with the cooked fennel and onion, letting it cook for just 30 seconds. Add the tomato paste and chili peppers next, and stir as it cooks an additional minute. Pour in white wine and let it bubble for a couple of minutes.
06 -
Mix in the tomato purée, sausage, oregano, and heavy cream. Scoop out a cup of pasta water and pour it into the sauce. Give it all a good stir, keep it on a steady simmer over medium-low, and let it thicken for about 5 minutes, checking on it now and then.
07 -
Drain the pasta and toss it back in the pot. Pour the sauce in and gently mix the two until well coated. Stir in the parmesan a bit at a time so it melts into the sauce. If it's too thick, add more pasta water a little at a time. Do a final taste and season with salt if it needs it. Top it off with cracked pepper and more parmesan before serving.