Set a large pot or Dutch oven over medium-high heat. Add the sausage (if using links, remove the casings first). Break it apart with a wooden spoon and cook until browned and crispy, about 5–7 minutes. Use a slotted spoon to remove the sausage and set it aside, leaving the rendered fat in the pot.

Turn the heat down to medium. Add your thinly sliced onions to the sausage fat. Cook them low and slow, stirring occasionally, for about 12–15 minutes.

Add the minced garlic to the onions and cook for just 1 minute until fragrant. Pour in a splash of the chicken bone broth to scrape up any brown bits from the bottom of the pot.

Add the rest of the chicken bone broth and bring it to a rolling boil. Stir in your pasta. Reduce the heat to medium-low, cover, and let it simmer. Set your timer for 13 minutes.

When there are about 5 minutes left on the timer, toss the chopped asparagus right on top of the pasta. Put the lid back on to let them steam-cook until tender-crisp.

Once the pasta is cooked and most of the liquid has been absorbed (it should look saucy, not soupy), turn off the heat. Stir in the heavy cream and parmesan cheese. Then add in the sausage and season with salt and pepper to taste.