I looked at the Argo website and they recommend nearly identical proportions. I would have said at first glance that there is too much in this recipe. Maybe it uses so much to make the recipe quick. But then the recipe also becomes time sensitive as you discovered. I think the flavor and texture will suffer from uncooked corn starch. I would use less and cook more.
Hi Gene ~ thanks for the response and checking the Argo website. I think I’ll look for a different recipe, but definitely cut back a bit on the cornstarch.