From Jennifer McLagan, author of three best-selling cookbooks: Bones, Fat and Odd Bits.
The simple act of making butter will give you an insight into the magical transformation of cream into butter and show you just how good fresh butter can taste. Whipping cream with 35 percent butterfat will work, but if you can get cream with a higher fat content, it will produce a richer butter. (Vital Green Farms makes whipping cream that’s 52 percent butterfat. Find it at the Calgary Farmers’ Market.)
2 c. good-quality high-fat whipping cream
1/2 t. fine sea salt (optional)
Pour the cream into a bowl of a stand mixer and let it warm up to about 60°F. Using the whisk attachment, whip the cream on medium-low speed. The cream will thicken, become stiff, and then start to break down. After 7 to 15 minutes, depending on the cream, it will separate into a milky liquid and globules of fat, and the latter will collect on the whisk. Stop whisking.
Remove the pieces of butter from the whisk and place them in a fine-mesh sieve. Strain the liquid from the bowl through the sieve. This liquid is true buttermilk, and you can drink it. Rinse the pieces of butter under cold running water until the water runs clear. This rinses off the remaining whey, which could turn the butter rancid.
Using your hands, squeeze the butter hard to remove the excess water. Place it on a work surface and knead it with your hands and a dough scraper to remove any remaining water.
If you prefer salted butter, work the salt into the soft butter with your hands. Using your hands, shape the butter as you like, wrap it well, and refrigerate. The butter will keep for up to a week. Makes about 3/4 cup.