Step 1

Heat olive oil in a large, deep skillet over medium heat. Cook and stir onion with a pinch of salt in hot oil until onion is soft and golden, 5 to 7 minutes. Stir sausage into onions; cook and stir until sausage is broken up and browned, 5 to 7 minutes.

Step 2

Pour 1 1/2 cups chicken broth into sausage mixture and bring to a boil while scraping the browned bits of food off of the bottom of the pan with a wooden spoon. Add orecchiette pasta; cook and stir pasta in hot broth, adding remaining broth when liquid is absorbed, until pasta is cooked through and most of the broth is absorbed, about 15 minutes.

Step 3

Stir arugula into pasta-sausage mixture until arugula wilts. Ladle pasta into bowls and dust with Parmigiano-Reggiano cheese.