You might be skeptical that the sugar will completely dissolve in this recipe without the use of heat. But it really works! The key is to shake up the drink really well (about 30-60 seconds) before popping it in the fridge for a short rest. After about fifteen minutes (or less) we can check the bottom of the glass to see if there's any sugar left. It should be completely dissolved at this point. Give it another shake or two and enjoy!