Make fresh homemade butter from heavy cream using a hand mixer. The cream separates into yellow butter and liquid buttermilk, giving you two useful homemade ingredients.
Beat the cream with a hand mixer for about 10 minutes. The cream will first become whipped, then turn grainy as the butter begins to form.
Just before the butter starts to separate, cover the bowl with cling film. Make a small opening in the center for the mixer beaters. Continue mixing through the opening to prevent the buttermilk from splashing.
Keep mixing until the yellow butter solids have completely separated from the liquid buttermilk.
Remove the cling film and pour the buttermilk into a separate bowl.
Gather the butter together, then place it in cold water.
Press and rinse the butter to remove the remaining buttermilk. Drain the cloudy water and replace it with fresh cold water. Repeat until the water runs clear.
Transfer the butter to parchment paper and shape it into a block.
Sprinkle a pinch of sea salt over the shaped butter, if using.
Wrap the butter securely in the parchment paper and refrigerate until firm.
Notes
Follow the Changes in Texture: I watch the cream carefully as it moves from whipped to grainy. The grainy appearance tells me that the butter is beginning to form. Cover Before the Liquid Separates: I add the cling film just before separation because the buttermilk can splash once it releases from the butter solids. Rinse Until the Water Stays Clear: When the water turns cloudy, I drain it and add fresh cold water. I continue until the water remains clear so no visible buttermilk is left behind. Season After Shaping: I shape the butter into a block before sprinkling over the sea salt. When I want unsalted butter, I simply leave it plain.