I use the curved/bladed side of the knife to spread, but I just saw a short video where a person used the flat side to spread peanut butter. It wasn't an instructional video in any way, but it did make me think, Hmm, the flat side matches the flat surface of the bread.
Bullgrit
The spreadable material typically isn't evenly distributed on the knife, and it is easier to manipulate the curved side into a smaller or larger spreading surface than the flat side, which typically utilizes either the entire length of the knife or just the tip.I use the curved/bladed side of the knife to spread, but I just saw a short video where a person used the flat side to spread peanut butter. It wasn't an instructional video in any way, but it did make me think, Hmm, the flat side matches the flat surface of the bread.
Bullgrit