I followed the author's advice and increased the recipe by 50% so that I could frost a round 9-inch 2-layer cake generously. I still had some left over. One of my guests said she liked the frosting because it wasn't too sweet; the sour cream gives it a little tang. I served this cake outdoors in the shade when it was about 85F out and the frosting held up pretty well; it didn't melt or weep.