I'm having some trouble with my cedar plank salmon. I preheated the dome to 350 and threw it on direct. Figured it would be done in around 20 minutes. When I checked the temp after 20 minutes, the thermometer barely even registered an increase from room temperature. Granted this is an unusually thick piece of salmon, probably over two inches at the center, and even the sides aren't too much below that; still, it surprised me. I put it back in for another 7 or 8 minutes or so. Checked it again, and the internal temp at the thickest part read 110. Another 5 minutes and the internal temp was at about 120. I understand it's a thick piece of fish, but does it generally take this long to cook through a thick piece of fish?