I'm American, using proper english (ie.- not adding extraneous 'u's in places they don't belong), and it is Tas-a-lak, like you say.
I do love it when foreigners try to tell me how my own language should be spelt. Arrogantly dictating that their deviations are the correct way of doing things, it takes a certain level of cheek.
The U's are not extraneous, they affect the way the word is pronounced if you spoke or understood proper English you would appreciate that. American simplified English simply spells words in what is little more than text speak, meaningless detractions from the correct spelling in an attempt to make the language easier to understand.