Inthe bowl of an electric mixerusing the whip attachment, beat the cream on high speed until curds and liquid form—approximately 5-6 minutes. Cover the bowl while whipping with a clean kitchen towel to prevent the cream from spraying out.
Pour the mixture through a cheese cloth-lined sieve set over a bowl. Gather the cheesecloth and squeeze to remove the whey.
Place the butterstill in the cheesecloth, into a bowl of ice water to firm. Remove the butter from the water, and after removing the cheesecloth, place the butter into a bowl.
Keep butter plain or flavor the butter as you wish using pestoherbs, citrus zest, spices, preserves, maple syrup, or other flavorings. Pack into a container and cover with plastic wrap.