*Cook’s Note: The corn starch helps to brown the beef and thicken the sauce once the sauce is added to the pan. But I’ve made this plenty of times without it; the sauce thickens as it reduces, albeit not as thick. It tastes delicious regardless. And make sure to shake off excess corn starch. It’s not a batter, you just want to lightly coat or dust the beef. If you are not using starch, you do not need to add water to the sauce. Additionally, you can use low-sodium tamari (or half/half) to further reduce the sodium content.