A couple of years ago after reading so much about trans fats I decided take the leap from margarine to butter. I was a reluctant convert: butter costs much more, and I had been a dedicated margarine user all my life, mainly for that reason. Butter was inconvenient at first—it's rock hard out of the fridge and it was different to work with in baking. But for quite awhile after I had all that figured out, I was still buying margarine in tubs from the store, because it's so hard to give up the convenience of having something spreadable right out of the fridge.
Then my mom sent me a recipe for spreadable butter. I made my first batch with extra virgin olive oil and it had a very distinct olive-oily taste that I didn't like—but the texture was right on. Just a minute or two at room temperature makes it quite easy to spread (leave it out all afternoon and it gets too melty!). So I made it again with light olive oil (and I'm sure any neutral-flavored oil would work just as well) and I had success. Now instead of buying questionable tub margarine to spread on bread, I just whip up a batch of this (it takes less than five minutes) and we're set.
Amazing bread recipe to follow tomorrow!
Whipped Spreadable Butter
2 sticks butter, completely soft (let them sit out for a day beforehand)
1 cup neutral-flavored oil such as "light" olive oil or canola oil
Using an electric mixer, whip butter on highest speed. Add oil a little at a time, stopping occasionally to scrape down bowl, until it has all been incorporated. Whip a few more minutes for good measure, until texture is uniform and gloopy.
Transfer to covered container and refrigerate.
Notes: If you're worried you won't like this, scale back the first time you try it. My first try was with 1/4 cup each butter and oil. Also, I think that a more powerful and thorough mixing job will incorporate more air and help your butter be more spreadable straight out of the fridge.