Thanks, This is a hard, shiny black crust-like build-up inside the cook chamber. I cannot get to it in some parts of the underside of the lid that is not exposed when it is open. I guess I will scrape off what I can and move it out into the open lawn area and crank it up and see if that will clean what I cannot reach.
It is concerning to me because I typically use it more during bad weather/rain. It is then used on our patio, under our deck, which is 9' above, and it is covered by the roof, another 10' up. If it ever had a creosote or grease fire, it would be bad. Many times, I will have it cooking and I will go do chores around the property, work in the barn, etc., and would not know I had a fire. I always cook on the top shelf with an aluminum pan below to catch drippings to help minimize the risk, plus easy clean up. But that creosote scares me. It took a heck of a lot of cooks over the years for it to start building up. I hope I can get it under control.
Thanks for the help.