every time i see butter written down in a recipe i hear my husband obnoxiously [love you] saying it in his best julia childs voice from the julie & julia movie [don't ask why he's seen that one either...] but seriously, one of the worst things is to get all inspired to make a great recipe only to find out that it calls for softened butter after you are 3/4 of the way through your recipe or beyond the point of turning back. you pop butter in the microwave, you end up with the valley in the center of somewhat melted butter and the rest so soft that it creates a hot & greasy mess as you open it. or almost even worse than that, you say screw it who the heck cares if its softened my kitchen aid mixer can cream it regardless ending up with large chunks and a burnt out mixer.
creaming butter & sugar together [as many recipes of baked goods require] should be the longest step of the entire recipe if you do it the way we are all actually supposed to. melted butter effects the consistency of the batter and the creaming process is essentially shot at that point. It really is recommended that if you melt the butter, that you put it in a small bowl and back in the fridge for your next baked potato or grilled cheese sandwich and start with a fresh stick. i will admit i've made a batch of muffins or two that ended up with grainy looking "creamed" butter and sugar versus the beautiful, slightly yellow lofted goodness a great recipe has.
in the ideal world we would all have the butter softened perfectly out of the wrapper and ready to go the moment we are ready to get baking. what i have found is that the days that i pull butter out, i don't end up baking...the days butter is frozen solid, its a matter of life or death for me to have a fresh sour cream pound cake...the solution?
all you need is a sandwich size ziploc bag. put your butter in there, and run some hot water over it for about 60 seconds, rotating the butter and the bag so that you don't end up with a hole where the stream of water poured onto the bag. within a minute of using not so scalding hot water, i've been able to soften my butter (from refrigerated temperatures) and creaming it with the sugar within minutes!