Using a wet measuring cup, pour heavy cream into the stand mixer.
Mix on medium speed until the cream just starts to thicken (beginning soft peaks). Add the sugar and vanilla extract.
Continue mixing on medium until the cream reaches stiff peaks. To test for stiff peaks, stop your mixer and pull the whisk straight up out of the cream. A peak will form and hold its shape straight up. You really need to pay attention here. Cream that is over whipped will have a grainy texture. Cream that is majorly over whipped will turn into butter.
Transfer cool whhip to a clean container. Use immediately or store in the refrigerator.
Notes
* You can also use a hand mixer or plain old whisk to make cool whhip. I personally don't have the patience or fortitude to whip cream by hand, so I use a stand mixer.