Go to C:\Users\<username>\AppData\LocalLow\Snowhound\PotionTycoon (<username> being your personal Username on your machine)

Open the settings.json file with Editor or a similar program.

Change the following line to your prefered resolution:

{
"key": "Video/Resolution",
"value": "XxY"
},

For example:

{
"key": "Video/Resolution",
"value": "3840x1600"
},

So far I have not seen any problems with the new resolution. Everything is where it should be.