Bring a large pot of lightly salted water
to boiling. Cook pasta according to
package directions. Drain and set aside.
Meanwhile, add walnuts to a large
nonstick sauté pan over medium heat; toast
5 minutes, stirring occasionally. Remove to
a cutting board to cool, then roughly chop.
In same pan, add chicken sausage. Cook
over medium heat 5 to 7 minutes, breaking
apart with a wooden spoon, until browned.
Stir in flour; cook 1 minute. Add broth and
bring to a simmer over medium-high heat.
Mix in apples and cook 2 minutes. Stir in
spinach until wilted. Mix in walnuts, Asiago,
salt and pepper. Transfer to a bowl with
pasta; stir to combine. Serve immediately.