How do you edit pinephone phosh desktop shortcuts/icons?

I like to play AisleRiot solitaire, but the locale is set wrong on the pinephone (it wants UTF-8, not ANSI).
If I type “LANG=en_US.utf8 sol” in the console it works great, so I would like to modify the command that occurs when I select it from the Phosh icon. How do i do this?