1. Remove casings from sausage, if necessary; crumble sausage into large skillet sprayed with cooking spray. Add onions; cook 15 min. or until sausage is done, stirring frequently. Meanwhile, cook pasta as directed on package, omitting salt.
2. Add arugula and broth to sausage mixture; cook 5 min. or until arugula is wilted and tender, stirring occasionally.
3. Drain pasta; place in large bowl. Add sausage mixture and cheese; mix lightly.
Special Extra: For a moister dish, reserve 1/4 cup of the water used to cook the pasta. Add to drained cooked pasta along with the sausage mixture and cheese.
Note: Two bunches of arugula should yield about 4 cups packed leaves.