Heat the sesame oil in a wok or other large nonstick skillet.
Add the red chillies and saute for a minute or so until they start to darken.
Add the ginger and garlic pastes and saute for a few seconds.
Add the vegetables and stir-fry on high heat, stirring constantly, about 2-3 minutes or until the vegetables begin to soften.
Now add the stock-soy sauce mixture in and allow it to come to a boil. Lower the heat and simmer a couple of minutes or until the veggies are cooked but have a good bite to them. You don't want your vegetables to turn soft and mushy.
Add the peanuts and stir in. Now add the cornstarch-water mixture, one teaspoon at a time, until you have a sauce that's fairly thick. Do NOT add the cornstarch at once-- watch your recipe closely and add only as much as you need.
Check for salt and add if needed. Add the scallions and give it a quick stir. Turn off heat and serve hot.