I have all the dry ingredients for the wasc cake and when I'm getting ready to get the wet ingredients ready I realized that I forgot to buy sour cream, I do have fat free plain yogurt, do you think I could substitute the sour cream with that???

Thanks.

. . . that would be a suitable substitution . . . did you already go ahead and do it . . . .

You sure can, in fact any type of yogurt substituted for the sour cream in a WASC is good. Peach is my hubby's favorite.