I was in Panama last week and bought some "anaerobic" beans. They smell delicious but sadly I have gone through almost the entire bag using my Breville Touch without one usable shot.

The shots come out GUSHING even on the finest setting. My grinder also seems to choke/click when I grind them very fine. Should I adjust the internal burr? I've never done this, how does that change my external grind setting?

I am trying 18g in, 36 out. But getting almost 40+ grams in 10 seconds.

I basically have one more shot at this... any help would be appreciated!

You have to be able to choke the machine, or nearly so, with a really fine grind to be able to make espresso. In this context, choking means that when you try to pull a shot, nothing comes out, or only a few drops. Once you've accomplished that, it's just a matter of gradually backing the grind setting off (turn the grinder a bit coarser) until you achieve the desired amount of coffee over the amount of time you want (usually 20 to 30 seconds).

I gather from your post, that when you try to do this something goes wrong with your grinder, which you describe a choke/click. I don't know what that means. In any case, if your grinder can't grind those beans finely enough, the results will be as you describe. This begs the question, whether your grinder can choke your machine with other beans. If it can, then likely the issue is with the beans.

Yes.. adjust the internal burr. What you are experiencing is not that uncommon. If you look in your manual (or get the online one) see the Burr adjustment section. It shows how to adjust.. (I think the upper) burr a bit. And this will allow you to grind in a finer range. Go one setting change at a time on the 'internal' adjustment and then set your outer adjustment up at least 5-10 settings so you have some room. If this isn't close, adjust the internal one even finer.. Adjusting the internal burr just gives you more range in the fineness of your grind.. It will mean you will lose some ability in the coarsest setting.. but this generally isn't a big deal unless you are doing a manual brew method that needs a very coarse grind.

You won't get this in one more trial..