cold pour oven process
means pouring your (traced) soap "batter" into the mold then sticking it in the oven to gel and saponify.
I'm not confident that the pringles can is capable of standing oven temps, but probably is. BUT
- is your oven tall enough to hold the mold standing up?
- vertical molds get hotter than horizontal (typically) so you run a higher risk of overheating.