Cook the pasta to al dente according to the package directions; drain and set aside.
Meanwhile, add the oil to a large skillet over medium-high heat. Add the sausage and onion and cook (uncovered) 5 minutes, stirring occasionally to break up the sausage. Stir in the apple, garlic, and frozen spinach, and cook (uncovered) until the apple is tender and the liquid is mostly evaporated off, about 6 to 8 minutes. Stir in the cream, salt, black pepper, and pasta; turn off the heat.
Sprinkle the fresh sage on top (or stir it in if you’re using dried) and serve along with fresh-grated Parmesan cheese for topping.
Recipe by An Edible Mosaic™ at https://www.anediblemosaic.com/gluten-free-penne-pasta-with-chicken-sausage-sage-and-apple-cream-sauce/