I would say go straight across, but warn you - depending on how the butter is used in the recipe you will probably not get anything close to the same result butter (or another solid fat) would give you. Some recipes might get you something edible in the end, some may not.
"Health nuts are going to feel stupid one day, lying in the hospital dying of nothing" -Redd Foxx
mix the sam amount of oil but do this
put the eggs for the recipe in a blender add a little sugar and add the oil very slowly at first yes you guess it make a sort of a mayonesse and then proceed with the recipe this emulsifying will help.
let me kow how it turns out firstname.lastname@example.org