Hi Mario,
I don't know how Authentic you want but this is easy and good. I have made it tons and will give you some adds at the end. PS posted this over on the make ahead board, I used her copy to cut & paste for you here, My orig. crdits Gloria Phietsr whomever she is ...

Olive Garden Alfredo Fettucine
8 ounces Cream cheese -- cut in bits
3/4 cup Parmesan cheese -- grated
1/2 cup Butter or margarine
1/2 cup Milk
8 ounces Fettuccine; cook -- drain In large
saucepan combine cream cheese, Parmesan,
butter and milk, stirring constantly until
smooth. Toss pasta lightly with sauce, coating
well. Leftovers freeze well. DO NOT BOIL sauce, watch it!!

I add to this sauted stuff, depending on my bugdget AND I think it was gustoff or geoff who said to add blue cheese and janie(?) offered the idea of using cream or 1/2 & 1/2 i have done all and each is GREAT so recipe is easy to change ... if adding cream do use some milk Oh and use fresh parmesean or romano ...
i add a little garlic as well.
mushrooms, bay scoolops, salad shrimp
julliane ham lucheon meat, zuccini, red onion, mushrooms
chicken pieces, ham, vege's I don't care for chicken in it though.
saute any of the above and add at the end or for a party you could do a big batch of plain sauce and divide amung differeing adds ... do add a little crumbled blue cheese it really was nice
Happy Birthday!
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