Trouble Measuring the Temperature of Meat My wife recently bought me a thermapen and I have used it a number of times to achieve perfectly roasted chicken and turkey, but I have trouble whenever I pan sear meat.
For example, tonight I tried to pan sear a NY strip using a cast iron skillet while basting with butter and herbs. I cooked the steak for about 10 minutes and the thermapen never registered a temperature above 105 degrees. When I cut the steak open it was dry and very well done. 

I've also had this problem with chicken breast. I can pan sear it, flip it after 6 minutes, observe a beautiful golden brown crust and when I insert the thermapen just below the surface of the chicken it reads less the 100 degrees. Surely the chicken is not cooling down rapidly?

If I wait until the thermapen registers 160 to stop cooking the chicken, it's totally dry inside. The fact that this happens with both chicken and steak makes me feel like I'm doing something wrong. I've followed the technique from Grilling Perfect Steaks Every Time, Every Steak , and I've also observed that the temperature will drop continuously as I pull the thermapen through the meat after it's been flipped once.
In other words, the minimum temperature is not at the center but on the side of the meat not in contact with the pan, even if it looks perfectly seared.

I know it isn't possible for the meat to cool down that quickly, so I don't understand what's happening. What's going on? Does anyone have any suggestions or know what I might be doing wrong?
I don't have enough reputation to put this as a comment. 

Have you checked the calibration on your thermopen? 

The instructions are here

Briefly:  


in ice water your thermopen should read 32F
in boiling water your thermopen should read about 212F (depends on altitude)


Additionally, very thin meats will be difficult to measure.