Them's spuds got some size to'em. Poke'em with a fork several times before wrapping and cooking next time. That should help a bit. Also, regardless of what you're cooking that you're wrapping in tin foil, make sure that whatever it is, is against the "shiny" side of the tin foil. Yeah I know, tin foil is shiny as it is, but one side is duller than the other for a reason, the "shiny" side will reflect some of the heat, the duller side lets it through. (there are those out there who don't know that)