Ya Comimos is a poetic Judeo Spanish or Ladino prayer said after the recital of Birkat Hamazon. It can be found in some birchonim, some Spanish and Portuguese siddurim and some Haggadot.
This prayer has form somewhat similar to Bendigamos, and shares some elements with the content of the Birkat Hamazon.
References
Ya Comimos Wikipedia(Text) CC BY-SA