Cooking a filet mignon perfectly is easy to do by using the sous vide method. I use an insulated styrofoam, digital stick thermometer and a plastic freezer bag. This is a home made setup sometimes called a "ghetto" sous vide.
Step by step:
Trim excess fat from filet and season w/ salt and pepper.
Place filet into freezer bag and remove air.
Submerge the filet in the140-145° water for 1 hour and 45 minutes. Take it out of the bag and dry completely and re-season.
Sear in a very hot pan for 2 minutes on each side to finish.
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