Step 1: Brown the Italian Sausage - Set a large pot or deep skillet over medium high heat and add the Italian sausage. Cook it until browned, using a wooden spoon to break it into small crumbles as it cooks. Smaller pieces spread more evenly through the pasta, which means you get a little sausage in nearly every bite. Once no pink remains and the edges have started to brown, transfer the sausage to a plate. If the pot has a large amount of grease, carefully drain most of it, but leave a light coating behind for flavor.
Step 2: Soften the Onion and Garlic - Add the diced onion to the same pot with a small drizzle of oil from the sun dried tomato jar. Stir and cook for three to four minutes, until the onion looks soft and slightly translucent. Scrape the bottom of the pot as you stir so the browned sausage bits loosen and become part of the sauce. Add the minced garlic and chopped sun dried tomatoes, then cook for about one minute. You want the garlic fragrant but not dark, since burned garlic can make the whole pot taste bitter.
Step 3: Add the Meat, Pasta, Broth, and Seasonings - Return the browned sausage to the pot, then add the chopped cooked bacon. Pour in the rotini and beef broth, followed by the salt, black pepper, garlic powder, and Italian seasoning. Stir slowly and thoroughly, making sure the pasta is mostly tucked beneath the liquid. It may look a little brothy at this stage, and that is exactly right. The pasta needs enough liquid to soften, and it will absorb a good portion of the broth as it cooks.
Step 4: Simmer Until the Pasta Is Tender - Bring the pot to a gentle boil, then lower the heat so the liquid settles into a steady simmer. Cover the pot and cook for about eighteen to twenty minutes. Stir once or twice during cooking, especially near the bottom, to keep the pasta from sticking. Begin checking around the eighteen minute mark. The rotini should be tender but still hold its shape, and there should still be some creamy looking broth in the pot. Do not cook until every drop of liquid disappears because the sauce will continue to thicken.
Step 5: Stir in the Cream and Kale - Pour in the heavy cream and stir until the broth changes from deep brown to a warm, creamy color. Add the chopped kale and cook for about three minutes, stirring occasionally. The kale should wilt and soften but still keep a little color. If your family prefers very soft greens, give it another minute or two. At this point, the kitchen will smell like sausage, garlic, and smoky bacon, which is usually when everyone starts asking how soon dinner will be ready.
Step 6: Melt in the Parmesan and Rest the Pasta - Sprinkle in the grated Parmesan, turn off the heat, and stir until the cheese melts into the sauce. Let the pasta rest uncovered for three to five minutes. This small pause matters because the sauce thickens as the starch, cream, and cheese settle together. Taste a bite and add more salt or black pepper only if needed. Spoon the pasta into bowls while it is warm, then finish with extra Parmesan and crushed red pepper flakes for anyone who wants them.