Bring a large pot of water to boil. Cook fettuccine according to package directions.
Meanwhile heat a large skillet over medium high heat.
Add olive oil, swirling to coat.
Slice sausage links into coins. Add to pan and cook for 4-5 minutes until lightly browned. Remove from pan.
Reduce heat to medium. Add butter to the pan. Once melted add garlic, and saute for a minute until fragrant. Be careful not to burn it.
Pour in heavy cream and Parmesan cheese. Whisk until smooth. Bring to a low simmer. Season with salt and pepper. Let cook for 1-2 minutes until it starts to thicken.
Stir in cooked sausage and pasta.
Top with additional Parmesan cheese and crushed red pepper flakes if desired.