new to tofu

do you have any suggestions/tips for preparing crispy tofu? i'd like to make a dish similar to p.f. chang's marvelous ma po. online researching has left me bewildered. some say use extra-firm tofu, others say medium or soft. most say to press out the moisture but this recipe for ma po says to boil the tofu first, and it doesn't specify the firmness. others suggest to freeze then thaw tofu before cooking. help, i'm tofuddled!

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