There are 2 versions I've tried: a regular one and a lower-fat one that was less rich but still tasty.
For the regular one, use:
1/4 c. butter
1 c. heavy cream
1 clove of minced garlic or a shake of garlic powder
1 c. parmesan cheese
1/2 c. mozarella cheese
I heated the butter, garlic and cream on med-low heat until the butter melted, then stirred in the cheese until it melted. Threw in a bunch of cracked pepper, a few shakes of salt, and a splash of the wine I was drinking. I let it heat for a minute, while stirring, and served it over penne rice pasta, since those are the only noodles I had. I sprinkled some parsley over it one time, and some italian seasonings another time. Both tasted good.
For the lower fat one, I used:
3 T. butter
2 T. GF flour
1 c. milk
same amounts of garlic & cheeses
I melted the butter, then stirred in the flour until it formed a paste. I slowly stirred in the milk and heated that up for a minute. I threw in the cheese and other ingredients the same way as before. If you are drinking wine (as I do when I cook), splash a bit of that in too. The wine will help to keep the mixture smooth. Since it's a white sauce I would use a white wine. Put it over pasta and enjoy!
P.S. A small hunk of cream cheese will help make the second version thicker as well
