By Johnisha Levi, americastestkitchenfeed.com

A few days back, I received a two-part bak­ing ques­tion on our Tum­blr blog from “redblackapron.” She asked: “Is there a rea­son why some blondie and brown­ie recipes require melt­ed but­ter, and oth­ers require just soft but­ter (at room…