Drain garbanzo beans and keep the liquid (aquafaba). Set beans aside for another use. Add aquafaba (I use all of what was in the can) to a mixing bowl (I used a stand mixer).  Mix on high for 5 minutes, or until mixture begins to foam.  Add cream of tartar, vanilla extract, and powdered sugar.  Mix for a few minutes more until soft peaks begin to form, about 3-5 minutes.  Taste for sweetness and adjust to preference. Do not overmix, or the whipped cream will fall and flatten out.