Butter is incredibly easy to make. Cooking for Engineers has a lovely post on making butter--it talks about benefits of butter, the science behind making butter, and also about the "traditional" way of making butter. They use a stand mixer, but this is definitely not a requirement. In fact, it's something you can do as easily with kids as you can do with your dinner guests, or on your own. Since we had whipping cream to go with our butternut squash soup (that post will appear soon), I asked E if she wanted to make fresh butter to go on the fresh bread.
E was skeptical. I think she imagined a butter churn. I told her I'd made it with the kids I was nannying over the summer, and that they were 2 and 5. This convinced E that it wouldn't be so bad (especially after I assured her we had plenty of cream for making whipped cream for the brownies I'd made her and for the soup, which was our real reason for buying whipping cream.) I love guilt-trips.
We poured cold whipping cream into a small jar and screwed on the top. E started agitating (shaking) the jar. After a bit--when we both thought maybe she'd been shaking it too long, we opened the jar, looked at the thickening cream, and poured off half the jar (about 1/2 cup--it'd started off with just about a cup) so that the process would go faster. E passed the jar off to our friend Caitlin, who was at our place for dinner and Caitlin diligently shook the jar. It finally started to form a very thick cream and then, very soon after that, butter and buttermilk. We added some salt, and Caitlin shook it a while longer. Then we scooped out the butter and got rid of the buttermilk (though you could use it -- I might recommend pour it off before you add the salt if you want to do that).
Then we added the other 1/2 cup back in and E had the opportunity to finish making butter. It went faster this time, in part because the cream was even colder (I'd stuck it in the freezer) and in part because there was less in the jar, and was therefore easier to agitate. At one point, E looked at me and said "I think it turned back into cream!"
What had, in fact, happened was that the butterfat and buttermilk separated. I got her to shake it a little longer and then we added salt and she finished shaking her butter. We spooned it out and put it on the same dish as Caitlin's butter--just in time for the hot bread and butternut squash soup.
All-in-all the entire process, both sets of butter probably took a collective 15-20 minutes. We had soft butter on the table and it was satisfying to spread fresh butter on my gluten-free bread--and I think fun to have a pretty much completely homemade meal, right down to the butter.
Although we used a jar to make butter, you can also whip it with a whisk or fork. In the past, I've accidentally created (literally sweet) butter by over-whipping air into whipped cream. Oops. But a kind of happy mistake that I spread on waffles a few days later.
Pour a small amount of very cold whipping cream into a small jar that can be closed with a lid. Close the jar and shake until a ball of butter begins to form, about 5-10 minutes, depending on the amount of cream you used.
Pour off the buttermilk, add salt, and shake or stir in. Pour off any additional buttermilk. Chill in the refrigerator to help it firm up, if desired. Keep any butter you don't use in a sealed container, in the refrigerator, on in a butter bell.