'Sing we Yule til Candlemas!': a medieval carol for the Twelve Days of Christmas - and beyond http://aclerkofoxford.blogspot.co.uk/2013/12/sing-we-yule-til-candlemas.html

Carols, plays, and 12 days of feasting: if you're celebrating a medieval-style Christmas, the fun is only just beginning... https://catholicherald.co.uk/feast-like-its-1399/

'The second day we sing of Stephen,
Who stoned was and rose up even
To God whom he saw stand in heaven,
And crowned was for his prowess.'

Image of the martyrdom of St Stephen, from the Benedictional of St Æthelwold (BL Add. 49598, f.17v)

St Stephen in red and gold, from an Anglo-Saxon liturgical manuscript (BL Cotton Caligula A XIV, f. 3v) http://www.bl.uk/onlinegallery/onlineex/illmanus/cottmanucoll/s/011cotcala00014u00003v00.html

The most famous carol for St Stephen's Day is 'Good King Wenceslas', but Stephen had his own songs too. This 15th-century ballad tells the legend of Stephen, King Herod, and a miraculous cooked bird... http://www.hymnsandcarolsofchristmas.com/Hymns_and_Carols/saint_stephen_was_a_clerk.htm

Another version of the story:

There are also ballads about St Stephen and Herod from Scandinavia, which have similarities to the English legendary ballads. In this tradition, Stephen is often Herod's stable-boy. Lots of different versions here: http://balladspot.blogspot.com/2017/12/staffansvisan-staffan-stalledrang.html

And this is another English traditional song about St Stephen, collected in the early 19th century. (Not so much poultry here.) https://mainlynorfolk.info/peter.bellamy/songs/saintstephen.html