Trying to keep my very picky eater 3yo healthy as we’re (hopefully) expanding his diet. Right now the only foods I can get him to actually eat are McDonald’s, a specific brand of yogurt, banana bread, some crackers and some bars. Refuses any beverage besides water. (He’s likely on the spectrum.)
Try him with a mcdonalds thickshake. If it comes in the cup from there… then you can do the cup trick.