Well sbc_and _reformed (hey can I call you SAR that's a long bit of typing there [img]http://www.the-highway.com/w3timages/icons/grin.gif" alt="grin" title="grin[/img]) would you say that their desserts were characterized by iniquity? Because that is what that adjective sinful means (although I suppose their use would be an adverb modifying the verb rich). Did you feel that you were committing gluttony? If so then perhaps their use of sinfully is justified.