Whip the cream

• Pour the cold heavy cream into the bowl of the stand mixer.
• Whip on medium-high speed until it thickens into whipped cream.

Keep whipping until the butter separates

• Continue whipping; the cream will break and separate into butterfat and buttermilk.
• Scrape down the sides of the bowl as needed.

Drain the buttermilk

• Pour off the buttermilk through a colander, saving it for another use.
• Press the butter against the colander to release the remaining liquid.

Rinse and knead the butter

• Rinse the butter under very cold water, kneading it with a spatula until the water runs clear.
• This removes all buttermilk so the butter keeps longer.

Season and store

• Knead in the salt if using.
• Shape the butter and wrap it, or pack it into a jar.
• Store in the fridge or freeze for longer keeping.