HOUSTON – The best part of a cappuccino or latte is the foamy milk on top. On this Test it Tuesday, we tested the Zulay Kitchen Milk Boss that claims it can do the job for just $20. Does the Milk Boss frothing gadget work? So you’ll have to heat the milk before you froth it with the Milk Boss. The Milk Boss comes in more than two dozen colors and you can use it to make matcha or Bulletproof Coffee.