Welcome to the EGGhead Forum - a great place to visit and packed with tips and EGGspert advice! You can also join the conversation and get more information and amazing recipes by following Big Green Egg at:
I almost always do flats. When I do find a packer, the price is higher than I want. Here is my last post on my method Flat out Tasty
This was a 8.5 lb flat. I start at 225° fat side down, we took it to the kitchen when the internal temp got to 165° and injected it with a beef broth, bouillon, worcestershire, and black pepper mixture. Bumped the egg up to 300° foiled it and start checking how easily the thermometer probe slides in and out at 195° and this one was much better at 205° so thats where we pulled it and put it in a cooler with towels for 2 hours.
Some guys don't inject or foil. But I do flats all the time and this was my method for the most tender one yet.