In a small bowl, whisk all the ingredients together.
In a large pan, saute a chopped onion in a bit of olive oil for about 5 minutes until it starts to brown. Add the rest of your veggies in order of how long they take to cook (peppers and mushrooms first, greens last).
Once the veggies are just cooked but not too soft, add the sauce to the pan. Mix well and allow the sauce to thicken for 1-2 minutes, then remove the pan from the heat and serve your stirfry hot.