Sliced kielbasa browned until the edges crisp, then simmered into a sauce of jarred marinara and heavy cream and tossed with rigatoni. Browning the sausage first is what gives the sauce its depth. About 30 minutes, start to finish.
Cook the pasta. Bring a large pot of salted water to a boil and cook the rigatoni to al dente, or a minute under. Reserve 1 cup of pasta water, then drain.
12 ounce Rigatoni pasta
Brown the kielbasa. While the pasta cooks, slice the sausage into ¼-inch rounds. Heat a little oil in a large skillet over medium and cook 5 to 7 minutes until the edges are browned. Remove and set aside, leaving the drippings in the pan.
2 tablespoon olive oil, 1 14 oz Kielbasa smoked sausage
Cook the aromatics. Add the onion and garlic to the same skillet and cook about 2 minutes, until soft and fragrant.
½ cup onion, finely chopped, 3 cloves garlic, minced
Build the sauce. Pour in the marinara, scraping up any browned bits from the bottom. Stir in the beef bouillon and simmer 5 to 7 minutes. Taste, and add sugar only if the sauce is sharp.
Add the cream. Lower the heat and stir in the heavy cream. Return the kielbasa and simmer gently 2 to 3 minutes. Don't let it boil.
1 cup heavy cream
Toss and serve. Add the drained pasta and toss to coat, loosening with reserved pasta water as needed. Top with parmesan and parsley.
½ cup parmesan cheese
Notes
Buy fully cooked smoked kielbasa, sold in a curved ring or a straight link. Fresh or white kielbasa is raw and won't work here, since this recipe assumes you're browning slices rather than cooking them through. Pork renders the most fat and browns best.
Brown the sausage properly, then take it out. It's already cooked, so this is purely for color and flavor. Give it 5 to 7 minutes without stirring constantly. Leaving it in while the sauce simmers softens the crisp edges you just made.
Don't wipe the pan between steps.The rendered fat and the browned bits on the bottom are what separate this from a jar of sauce with sausage in it. Scrape them up when the marinara goes in.
Keep the heat low once the cream is in. Cream that boils hard separates and goes grainy. After it's in the pan you're warming through, not simmering.
Save a cup of pasta water. The sauce keeps thickening between the stove and the table. A splash of starchy water loosens it without diluting the flavor.
Taste before adding sugar. Jarred marinara varies a lot. Some brands are sweet enough already that a pinch tips it over.
Undercook the pasta by a minute. It finishes in the sauce, and rigatoni that was right in the pot is soft by the time it's coated.
Substitutions. Half-and-half in place of heavy cream, though it's thinner and more likely to split. Cream cheese is sturdier, two ounces cubed and stirred in. Any fully cooked smoked sausage works instead of kielbasa: andouille, smoked turkey, or a generic smoked sausage ring.
Storage. Airtight in the fridge up to 3 days. The pasta absorbs sauce as it sits, so reheat gently on the stove with a splash of cream or milk. The sauce alone holds a day in the fridge if you want to make it ahead and cook the pasta fresh.