OOOH! I finally get to share the alfredo sauce recipe I developed for low fatness and good flavor, adapted in part from bechamil sauce out of Joy of Cooking:
1/2 cup flour
1/2 cup X virgin olive oil
Preheat oven to 250 degrees F / 100 degrees C
Set your oven proof pan (use one that has a good cover) corning ware can be used for this, on a burner set to medium or less, depending on your stove, when the temp has stabilized add the oil, when the oil has come to temperature, add the flour, stirring well until the mixture is homogeneous. Make a white roux, cooking the flour in the oil without browning it, the roux is finished when the raw flour taste is gone (um let it cool before tasting...hot oil and all). Note don't ever use wooden cooking tools to make roux, the wood will char and bits will break off making the roux bitter.
Now add milk (I use skimmed milk) and bring the temperature of the mixture up until the roux and milk have consolidated and the consistency is what you want. Take pan off burner for a bit whilst you make the next step.
Take a large onion, peel it and cut it in half, then stick 20 - 30 whole cloves into the onion near the flat base of the onion and place the onion in the white sauce (after it has cooled a bit, don't want to burn the onion or spice in the hot oil). Mince up fine garlic to taste, I usually use a half of a medium head of garlic but suit yourself, and add a by leaf. Put your ovenproof pan, covered into the oven for 3/4 hour. After time, take the pan out, remove the onion, bay leaf and any bits of clove which have broken off.
Turn oven down to 100 C / 212 F.
Season the sauce with what ever you like, I use a bit of Tabasco, salt and white pepper. Next take very thin slices or finely grated cheeses (thin slices work best) in smallish quantities and of various types and add them in to white sauce, carefully; DO NOT OVERWORK THE CHEESE if you do, you will wind up with stringy glops of cheese which will need to be fished out before this last step can be restarted. The last one of these I made had 1 ounce /28 gm of aged cheddar, 2 oz /56 gm of manchega, a bit of parmasan, and a bit of smoked gouda.
Put your pan back into the oven, checking in 1/2 hour and every 10 minutes after that to see if the cheese is disintegrating and becoming as liquid as the white sauce. Once this has happened, stir in the cheese gently, pulling any stringy globs off your mixing device, adjust seasoning and serve with whatever you want, parsley or cilantro on top is pretty, so is paprika, saffron, etc.
Not a true alfredo sauce, but has all the characteristics except the enormous saturated fat load.
Oh yeah, it isn't very expensive to make either.