Recipes always say to beat softened butter and sugar until pale and fluffy. I can never get this in my kitchenaid. Butter and sugar form a thick paste that coats the walls of the bowl where the beater barely touches, meaning I have to scrape the sides down every few seconds. First I thought maybe my butter wasn't softened enough, but today I tried again making sure my butter was properly softened, same results. Anyone else have this problem?