Good for you Roff, I'm so proud to have influenced your feast! Just keep slowly turning up the heat until it hold where you want it and you'll be fine. You won't ruin it trust me, there were almost tears in my eyes as my prime rib was a fireball, but the people raved, and honestly that fireball was almost worth the money to see...almost.
Trust me I've thrown caution to the wind countless time and haven't had to order Domino's yet!
Good Luck and Enjoy!

