I Don't know How i made this error but I did... I put one cup of egg whites, one cup of sugar and two cups of butter. I didn't notice until the cake was already Iced.... should I scrape it off and start over or will it be fine?
I did though add a little powered sugar to the icing, but not enough to equal to a cup.
If it performed fine and it tastes fine, you're good to go.