I was cooking ribs this weekend on my BGE. After about 5 hours, the ribs were done; I removed them from the grill, removed the heat diffusion plate, allowed the grill to heat up and then threw the chicken on. After checking the progress of the chicken for the second time, I shut the lid to the Big Green Egg and nearly closed the top damper. I heard a sudden rush of air, then a brief period of silence then BOOM. The top lid of the BGE lifted up about 2 inches and this huge smoke cloud rushed out from inside the grill. I then opened the grill. The chicken was intact but the lower gasket became unseated and was nearly fused to the top lid gasket. No lighter fluid was used to start the grill and the chicken was not marinated in alcohol. Any thoughts on what that explosion was all about?