Start to finish: 20 minutes
Makes about 1 pound butter
1 quart heavy cream, left at room temperature for 30 minutes
To use the food processor, pour the cream into the bowl fitted with either the plastic or metal blade. Process on high.
To use an electric mixer, pour the cream into the bowl and beat with the wire whip attachment. Use a deep bowl with a splatter guard if available.
Regardless of the method used, the cream will go through the same stages. At first the cream will thicken and be whipped into soft peaks, then firm peaks. Then the cream will begin to get grainy. Finally a liquid will be released so that you have lumps of fat in a milky colored liquid. The entire process should take five to 20 minutes, depending on the method used.
Rest a fine mesh strainer over a bowl and strain out the buttermilk. Reserve for another recipe. Place the butter in a bowl and knead with your hand to squeeze out any more buttermilk. It may seem odd to knead butter, but it will hold together and kneads easily.
You can use the butter immediately or refrigerate it for later. If storing for later, you’ll want to “wash” the butter. This helps remove even more buttermilk from the butter so it doesn’t sour. Add ½ cup of ice water to the butter in the bowl. Continue kneading the butter in the ice water. Pour off the milky liquid. Repeat the ice water wash and kneading process until the liquid remains clear.
If you’d like to keep unsalted butter (such as for baking), wrap the butter in parchment paper and then plastic wrap and refrigerate for two weeks or freeze for six months. Otherwise add salt, to taste, then wrap in parchment and plastic wrap. It also can be stored in an airtight container.
This is also a good point to add other flavorings, if desired, such as honey and cinnamon for toast and pancakes, or herbs and garlic for bread or meat.