The words "yummy princess" can be substituted with a variety of synonymic phrases. One option could be "delicious queen," which carries a similar regal connotation but with a stronger emphasis on tastiness. Another possibility is "tasty monarch," which combines the concepts of flavor and authority in a playful way. Other options might include "delectable empress," "scrumptious ruler," or "savory sovereign." Each of these alternatives offers a slightly different take on the same basic idea, but all convey a sense of deliciousness and royalty that captures the playful spirit of the original phrase.