In a large, deep skillet or Dutch oven, brown the Italian sausage over medium-high heat. Break it into crumbles but allow some pieces to get deeply browned and slightly crispy.

Add the sliced bell peppers to the sausage. Cook for 3–5 minutes until the peppers are tender-crisp and have picked up some of the savory fats from the meat.

Stir in the minced garlic, Italian seasoning, and red pepper flakes. Cook for just 30–60 seconds until the garlic is fragrant, being careful not to let it burn.

Pour the white wine into the hot pan. Use a wooden spoon to scrape the bottom of the skillet to release all the flavorful browned bits (the fond). Let the wine simmer and reduce by half; this concentrates the flavor and cooks off the sharp alcohol bite.

Add the diced tomatoes (with their juices) and the dried basil. Reduce heat to medium-low and let the sauce simmer for 8–10 minutes. This allows the tomatoes to break down and meld with the wine and sausage fats.

While the sauce simmers, boil your noodles in salted water until just al dente. Drain and add them directly into the skillet. Toss thoroughly to ensure the sauce penetrates the ridges of the noodles.

Turn off the heat and stir in the fresh parsley and half of the Parmesan cheese. The residual heat will melt the cheese into the sauce, making it silky.

Ladle into bowls and top with the remaining Parmesan.