Simple Potsticker Dipping Sauce

My family likes to eat the Ling Ling potstickers from Costco (or the grocery store when I have a great coupon).  We love the dipping sauce, but we never have enough to last through the large bag from Costco.  After looking at different recipes (simple, complex, spicy, etc), I concocted this, which we like.  It is very simple.

1/8 C (or 2T) soy sauce (any kind)
1 T vinegar  (I have only used white so far)
1 t sugar
Dash of red pepper flakes (optional)

Mix the above ingredients in a bowl.  Then dip.  Easy!