DocMando - Big Mick gave it to you correctly. A planxty is an honorific composition. Some of them might seem a bit horrific, but maybe that't the famous Irish love of satire.
Monsignor McGrath's humorous post is really just a subtle commercial. Many of us suspect that he's branched out and started a cook-book company. Don't know if he uses it to sell his oft-times riotous ditties, or the other way around. But at the very least, he's known for the "food for thought" woven through many of his posts. :>)