I plan on making stir fry a few times this week since it's so hot outside and don't feel like lighting the oven. However, I have a hard time getting a nice flavor out of my stir fry's unless I'm adding a bottled sauce or making a thai style curry. I just don't find much flavor in the simple soy sauce and garlic and ginger. Any suggestions on how to boost flavor without reaching for a sugary store bought sauce??