In a food processor or blender, add cream.
Start churning on a medium heat and increase to high as you go.
Churn till butter separates. It may take anywhere from 2-5 minutes or longer depending on whisk speed.
Once butter is separated, add salt if desired and add ice-cold water with ice and start collecting butter or use cheese cloth to strain butter quickly. If desired, extra rinse can be done to wash butter well.
Now, you can shape the butter however you like and store into refrigerator for up to 15 days or freeze for longer.
If desired, many flavors can be added to butter before refrigerating.
Enjoy butter however you like!