The green tea bubble cream cupcake sure sounds interesting. maybe find the liners at a party store?
I know for the holidays, even our walmart has seasonal cupcake liners, which I buy up when I see them. Right now lots of Valentine-ey stuff. I looked at the Grasshopper cupcake recipe and she calls for 1 tsp batter, then a mint, then 1/2 tsp batter to cover---for a regular cupcake. No way would that fill that liner enough. Maybe the UK tsp is larger.