There's symbolism in this drink, natch:
• it has 3 ingredients, befitting the famously triple goddess, Brighid
• one of them is dairy-based, connecting with the name #Oimelc, "ewes' milk", for the holiday
• the hazelnut liqueur connects with the usual Celtic symbolism of hazelnuts as bringers of knowledge and wisdom, necessary for a smith, a poet, or a healer
• then we set the whole thing on fire, as is only right and proper for a fire goddess 7/8