How much does Pancake make per year?

More than all of us.

My guess is 13.5-14 million baht ($409,672-$425,022 USD), considering she has to pay up 5 million baht in income tax. The income tax for individuals who make more than 4 million baht ($121,304 USD) and up in Thailand is 37%. Not too shabby when the average national income for Thais with an undergraduate degree is 84,000-108,000 baht ($2,548-$3,276 USD) per year according to wikianswer OR $7,000-8,000 USD according to other sources.

With her taxes paid, she would get to keep 8.5-9 million baht ($257,771-$272,934 USD).

Of course this guess is from simple math and even estimation, it is most likely off by a few thousand dollars.