Thanks to my friend, Ellen, I now use no-fat or low-fat yogurt instead of cream in several recipes . . . and it works GREAT!
When I want to use this substitution in something sweet, like scones, I use vanilla yogurt. (I tried a couple scone recipes. The “cream scone” recipe that mostly just involved cream – or in this case yogurt – and flour was not nearly as good as the more traditional recipe that called for a bit of butter and an egg.)
When I want to make the substitution in something savory, like quesadilla pie, I use plain yogurt.
Use the same amount of yogurt as the recipe calls for cream.
I won’t be trying it in anything like fettuccine alfredo any time soon; baked goods and casseroles are probably the limit of this substitution . . . but I was thrilled to make scones for the first time in years!

My aunt (a foodie) substitutes plain greek yogurt for sour cream in recipes. I think she said she brings it to a boil if she is going to cook with it first, but she swears it tastes really good.
Ooooh! Thanks, friend, I’ll try that one too! I can see that it would taste good! jen http://www.learningpatience.wordpress.com
Not to rain on the yogurt parade, but be careful before going whole hog with your substitutions. I once tried substituting all the heavy cream called for in a curry recipe, and the yogurt curdled. Ick! Maybe it got too hot all at once? I’ve never tried Anna’s aunt’s trick. Maybe the greek yogurt would’ve made the difference….
Hmmm, good to know! jen http://www.learningpatience.wordpress.com