Just How Soft is Softened Butter? (Tip for Making Buttercream Icings)

{I dedicate this post to Ellen and Courtney.}

I wanted to give you one all-important tip to consider when making buttercream icings.

It all has to do with the temperature of the butter.

Recipes for buttercream usually call for "softened" butter, or "butter at room temperature".  More recently, I've noticed that recipes are getting more specific and list "butter, at cool room temperature" or "butter, softened but still cool".  Confused yet?

It's simple really.  When using butter for cooked buttercream icings (meringue icings, French buttercreams, or boiled icings), the butter cannot be too warm, or the frosting will not set up properly and will probably stay a liquidy mess, not worthy of any cupcake.  (There are ways to try to remedy this if this should happen .)

For this reason, you should never, ever, microwave your butter to soften it - no matter how quickly you need the softened butter.  The microwave heats the butter unevenly and you'll have some cool spots, and other areas that are melted.  Your buttercream will reject you if you do this.

But if you only have cold butter on hand, you don't need to think ahead an hour before starting your buttercream either. When I start to make a buttercream icing, I pull my butter out of the refrigerator, unwrap it and slice each stick of butter into 6-10 pieces (or more - smaller pieces soften faster than large pieces),  making sure that the pieces of butter are mostly sitting by themselves and not touching each other too much. This increases the area of each piece that is exposed to the air, allowing them to soften faster.  By the time I have cooked the egg whites or sugar on the stove, and then whipped them until cool (about 20 minutes total), the butter is usually ready to go.

If you're looking to release some pent-up energy, you could pound on the stick of butter with a rolling pin until it is thin and let it stand for 20 minutes.  But be prepared to explain what that pounding is to the rest of the household.  I like to slice it, because you'll be adding the butter to the mixer in pieces anyway.

So how can you tell if the butter is ready?  Take a piece of butter between your thumb and finger and squeeze it a little.  You should be able to make an impression in the butter with your fingers, but it should still provide some resistance.  The butter should feel more waxy than greasy.  If the butter is still too cool (too hard to press into), wait a while longer.  Sometimes I'll flatten each piece with my hand before it goes into the mixer.  If it gives way without any resistance, the butter is too soft.  Get it back into the refrigerator for a few minutes until it passes the test.