Start by cooking the fettuccine pasta, according to the instructions listed on the back of the package. Drain, and set in a bowl once cooked.
Use a large skillet and add melted butter. Saute over medium heat. Add mushrooms, cooking and stirring for approximately 5 to 7 minutes or until tender.
Add garlic, continuing to stir for one minute. Then stir in the cream, sherry, stock, rosemary, thyme, basil, salt, pepper and cayenne.
Bring all of the ingredients to a boil, continuing to stir until reaching the desired thickness. This will take roughly 15-20 minutes.
Serve over fettuccine and enjoy! Garnish with parsley if desired.