During my several years in catering, I developed a method for buttering sandwiches.

I use ordinary butter, but I leave it out of the fridge, somewhere warm so that it's in that state of squishiness akin to custard, but not so melted that it goes clear and runny. I find it spreads easily and goes twice as far. The whole point of a sandwich is to taste the filling, not the spread so little is best.

LTS