Bring a large pot of salted water to a boil then cook the pasta until just tender and reserve a cup of the cooking water
Warm a wide skillet over medium heat then add olive oil and brown the sliced chicken sausage until edges turn golden remove to a plate
In the same skillet add onion and cook until soft add garlic and stir until the garlic smells nutty
Pour in the broth and scrape up the browned bits stir in the cream and simmer until the sauce looks smooth
Stir in parmesan until it melts slide the sausage back into the pan
Add the drained pasta and toss until coated splash in a little pasta water as needed for a loose glossy sauce
Fold in spinach until it wilts season with salt pepper and red pepper flakes
Serve hot with extra parmesan and a little lemon zest if you like