We have had Price's "Treasury" cookbook for 30 years and just love it. This Chocolate Butter Cream Frosting is the only one I use and has been the single most requested topping -for just about every cake I make- over the years. I make it as directed in his cookbook (steps include double-boiler not blender, cooling etc) and like the consistency better than with the blender, although this blender technique is certainly fast. I also use 70% bitter Cacao bars, crushed, for that outrageous bittersweet full-bodied chocolate flavor. Spread when the consistency is just thick enough to leave raised trails. I do find the frosting does much better if chilled. Remember too that this is a true butter cream and the frosting will begin to spoil if left out for more than a day.