It's much simpler than it looks! This was what stumped me for a while.
 

Only 4 Easy Steps

Hi! This is my initial guide, lol
 
I noticed that (was the only guide available. This may be because it is so easy to miss). If anyone else needs help with this one, please say hello! You've arrived at the right place.
 
 
Requirements:
 
– Lv 8+ Hobo Code Literacy
 
100 meats left over
 
 
 

Step 1 Finding Underground Fission Chips

Yes, this is where you'll be able achieve this achievement
 
It's at the S.I.T. Keep going through steam tunnels to find the door with the skull and crossbones.
 
 

 
 
 

Step 2: Hobo Code

To unlock this achievement, you'll need a translation of lv 8 hobo code.
 
 

 
 
 

Step 3 Go In and Purchase It

Straightforward, I think. You can buy the stuffed-pepper fish sandwich for just 100 meat
 
 

 
 

 
 
 

Step 4: Eat it

It's simple, you can just eat the cake and achieve your goal.
 
 

 
 
We hope this helps you!

 
 
This is all we know about Shadows Over Loathing – Getting the “Everything’s A Sandwich If You Believe” Achievement, this post original url can be found here and possible new updated to.