I have a routine every morning... I go to Seattle's Best at my local Borders to get a cup of coffee, and upon receiving it, I say thanks. While this sounds simple enough, I've employed these steps to create what I imagine to be a difficult Brain Game. Good luck:

By changing one letter at a time to form different English words, and leaving all other letters in their original positions, convert COFFEE into THANKS in the fewest number of steps possible. Good luck!

C O F F E E
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T H A N K S

Here is a 12-step SOLUTION.

A 12-STEP SOLUTION:

COFFEE > COFFER > CONFER > CONKER > COOKER > CHOKER >

CHOKES > CHORES > SHORES > SHARES > SHARKS > SHANKS > THANKS

Did you come up with a different solution? Please post it in the comments; thanks!