Instructions

1. Remove the cream from the refrigerator and put it in a warm place such as a sunny window for two hours, or until the cream reaches a temperature of about 60 degrees Fahrenheit. Don't allow cream to sit at room temperature for more than two hours because bacteria develop quickly when cream isn't refrigerated.

2. Scrub a sturdy, 1-quart glass jar with hot, soapy water. Rinse the jar thoroughly, then dry it with a clean towel. Be sure the jar has a tightly fitting screw-on lid.

3. Fill the jar halfway to the top with cream, then tighten the lid securely.

4. Holding the jar securely in both hands, shake the cream rapidly up and down without stopping for 15 to 20 minutes. Watch as the butter begins to separate and form a ball. Shake the jar slowly when butter begins to form; otherwise, you'll make whipped cream instead of butter.

5. Open the jar and pour the thin buttermilk into a jar or glass as soon as the mass of butter stops gathering. The buttermilk is safe to drink.

6. Transfer the butter to a mixing bowl along with a small handful of ice cubes. Wash your hands thoroughly in hot, soapy water. As the ice melts, use your hands or a wooden spoon to work the cold water into the mass of butter until the butter is firm and cold and the water is clear. Discard the ice cubes and water.

7. Sprinkle salt lightly over the butter, then use your hands to work the salt into the butter until the salt is no longer visible.

8. Shape the butter into a ball, or into any shape you like. Put the butter on a plate and store it in the refrigerator.