1. **Chill the Equipment**: For best results, chill the blender or food processor bowl and blades in the freezer for about 10 minutes before starting.
2. **Pour Cream into Blender**: Add the heavy cream to the chilled blender or food processor.
3. **Blend**: Start blending on a medium to high speed. After about 2 minutes, the cream will first turn into whipped cream. Keep blending, and you will soon see the butterfat separating from the buttermilk.
4. **Separate Butter from Buttermilk**: Once the butter has formed (it will look like clumps), stop the blender. Pour the contents into a bowl. The buttermilk will be the liquid that separates from the butter.
5. **Drain and Rinse**: Pour the butter into a cheesecloth or clean kitchen towel to drain excess buttermilk. You can also use a colander lined with cheesecloth. Rinse the butter under cold water, kneading and squeezing it to remove remaining buttermilk. This helps the butter last longer.
6. **Add Salt (Optional)**: If you like salted butter, knead in salt to taste.
7. **Store**: Transfer the butter to an airtight container and store it in the refrigerator. It should keep for about 1-2 weeks, or you can freeze it for longer storage.
### Note:
This method works well for making smaller batches. Making 1 kg of butter in 5 minutes would require very large equipment or multiple batches, as blending larger quantities could lead to uneven results or equipment strain. For large quantities, you may need a commercial butter churn or multiple sessions with a standard kitchen blender or processor.
Enjoy your homemade butter!