First, a note: this was mixed 50/50 with Adagio’s Currant tea.
I tried this plain, and it was too bitter and tannin-heavy. I added some sugar, and it was still too bold, so I tried a splash of milk. Perfect! The currant flavor masks a lot of the overpowering nature of Birthday, so the vanilla came out as an overtone very pleasantly. Still relatively one-dimensional, but hot and sweet and perfect for a birthday.