Cym: Slender Awl
Kulfanwyd is known from only two soruces, Triads 71 and 80 of the Trioedd Ynys Prydein and the Mabinogi of Culhwch ac Olwen Triad 80 gives the three daughters of Kulfanwyd Post Prydein as the three faithless wives of the Island of Britain: Esyllt Fyngwen Drysan's lover; Penarwan the wife of Owein son of Urien and Bun the wife of Fflamddwyn (literally flame-bearer who may have been Theoderic son of Ida the sixth century king of Berenicia). In the Peniarth 267 MSS version of Triad 71 Essyllt's father is given as Gyrrmananyd Post Prydain (Which is probably a mis-transcription of Kulfanwyd). It is also likely that the 'Prydain' element in Kulfanwyd's name was originally 'Prydyn' (Pictland) with a process of confusion ocurring when the tales were transferred from the Old North to the western lands of the Cymry so that the original 'Prydyn' becme 'Prydain' (Britain).
Kulfanwyd is also mentioned as one of the warriors of Arthur's court in the Mabinogi of Culhwch ac Olwen (Where he is named as Kulfanwyd mab Goryon. As Esyllt is also mentioned in the same time it is possible that the relationship between Esyllt and Kulfanwyd represents an old tradition.
Kulfanwyd's name is generally taken to be formed from the Brythonic components cul (thin, slender) and manwyd (awl), giving us 'Slender Awl' as an interpretation. Not a very flattering epithet, but as the father of a triad of faithless wives he could hardly hope to be portrayed in the best light.
If you would like to try the foods of the time of the ancient Celts, then why not have a look at the ancient recipes section of this site. For the foods of the time when some of these tales were written down, take a look at the Medieval recipes section of the site and, in particular, the recipes from The Forme of Cury.
