I would do some experimenting to find the right combination. Sometimes cornstarch is added to infant formula to keep blood sugars from dropping too low in babies with low blood sugars. This concept was originally developed for children with a disorder called glycogen storage disease.
Many patients require tube feeding at night to prevent low blood sugars during sleep.
Adding uncooked cornstarch to a nighttime snack helped some of these children come off nighttime tube feeding. If you add the cornstarch before you heat the pudding, it will work faster. Also, you have to be careful adding the cornstarch to soda if the pH is acid. Apparently this also interferes with the delayed action. I tell patients to start with a small amount of cornstarch, like 1 teaspoon and slowly increase the cornstarch as long as there is no diarrhea up to about 1 tablespoon at night.