Toast the sesame seeds in a pan and set aside.

Combine cornstarch and water in a bowl and mix together until smooth. Add the pork slices to the bowl and mix well. Heat 2 tablespoons of vegetable oil in a saute pan. Add the pork slices to the hot pan and cook until no longer pink. Transfer to a covered bowl and keep warm.

Using same pan add sesame oil (and remaining vegetable oil if necessary);add the sliced zucchini to the pan and cook for about 4-5 minutes.

Return pork to the pan and add sesame seeds, soy sauce (teriyaki) and stock. Mix well and cook (slightly covered) for about 3-4 minutes more-or until sauce thickens. Serve over warm rice.