That was quite fun! The mixing of the potions is an interesting mechanic and it works quite well!
My gripe is not with the game itself but with the tutorial of the game, it's a fair bit of reading and yet it doesn't actually tell you how to play :P I had to figure out how to interact with stuff and how to add/mix/heat stuff up by myself through trial and error, the tutorial told me I had to do it but not how to do it.
Which is sad because the art is this game is STUNNING!! Why not use some of that art for a dynamic intro that teaches you how to play? Some simple popups on screen that tell you what to do for the first customer or something?
In the end I had to give up because I am fairly certain I made the right potion but I cound't figure out how to pour it into a cup and give it to them because the game didn't tell me how and nothing I tried worked! I am also pretty sure I managed to push a cup and vial out of bounds at the bottom of the screen. lol
With a few tweaks this game can be really really good I think! The mechanics are solid and it's actually pretty engaging, I wanted to/would've played quite a bit more if I actually managed to figure out how to! So I hope you don't fully drop this after the jam and make some improvements on it cuz I see the potential it has!