“I should know how to do this simple thing!”

Maybe start with something simple, get that right and build on that. I've noticed a lot of people try and do something difficult to start with, I've taught several people to cook and many have done this. 

aurelis said:

However, I also think it would help me to give more time to prepare food before cooking

Yeah, me too. If I have to do something complicated with lots of ingredients and steps, I spend an hour or two just casually gathering things together, measuring then out into little dishes, chopping things, slicing things, putting them in little dishes, ("Another glass of wine?" "Sure, why not."), filling pots with water and bring them up to near boiling, assembling spatulas and spoons, etc. No rush with any of it. I even go full autistic on it and line everything up in the order in which they need to be added/used. Then, when the time comes, I cook like those TV chefs who have everything already prepared for them by some "kitchen assistant" or "food stylist".

Thank you for this, I always think my brain is broken all the time because I can’t adapt as easily. However, I also think it would help me to give more time to prepare food before cooking .

I think it’s a perfection thing. So I start shutting down when the process becomes confusing. And it affects me with going back to cooking again

Is it not partly a perfection thing?

If you soaked it a bit less, does it really matter?

Would you be able tell? You could still eat it.

Maybe just allow yourself the space for it to be ok, not perfect. You can do it better next time. Take the pressure off and enjoy the process as much as the end result.

aurelis said:

I don’t ask for help, feeling ashamed. “I should understand this, it’s so simple, why am I so stupid, come on!”

Our Autistic (or ADHD) brains just aren't very good at ignoring tiny inconsistencies in instructions. I was making a curry from a recipe that mentioned four chillies, two were to be chopped and and added while cooking and the other two were to be kept to the side. I read the recipe over and over again for ten minutes to figure out what to do with those other two chillies, but they were never mentioned again. Then I got stuck wondering what I was supposed to do now? Should I ignore the instruction? Just use two chillies instead of four? Slice those other chillies and use them as a garnish? Also cook the other two chillies? WHAT?! I had to confer with my wife and we decided to ignore them, only then could I move on.

Am I stupid? No. I just got stuck wondering what I was supposed to do next. I had too many options to work through and no way to prioritise them. This happens to me all the time. It happens to Autistic/ADHD folks all the time. Our "executive function", our ability to just decide to do something and go do it, is out of wack. It is very frustrating—EXTREMELY FRUSTRATING!!! —but it is not our fault and nothing to be ashamed of. It's just the way we are.

So, ask for help, have someone do things with you—your mum sounds great. Even just having a "body double", someone in the same room, can help a lot. Learn a few recipes off by heart, so you don't have to follow instructions every time and it just becomes your own way of doing things.

And go easy on yourself. You're not broken. Your brain is just a little different from a lot of the brains you see around you.

aurelis said:

if there is something that I don’t understand or doesn’t make sense, I overthink it until I shutdown.

I find a great way to nip this in the bud is to write down the problem - somehow capturing it on paper (often on a bunch of post-it notes) let me see where the grey areas are and lets me focus on these to the point I can finally see the whole thing in a way I can work with.

I spent a long career in IT Support and management and the problems I had to deal with should have been logical, defined issues but due to bugs, bad coding, malfunctioning hardware and, err, operator error, the problem were often very subtle to resolve.

I found by getting things down on paper in a Sherlock Holmes way I could eliminate different things and focus on those that remained until I had the solution.

As with your fish prep, somethines things end up like a spanner in the gears so you do need to step back, work through the mental capture process with the new information and see what needs to be done to progress again - sometimes you need to ask an outside party for advice or just accept that the fish may need a bit more salt when cooked or whatever.

Learning to accept things have changed and bend to those changes (using the technique above) has saved my sanity on countless complex issues over the years so it may be worth a try.

I think anyone who's tried assembling a piece of flatpack furniture will relate to this!

I'm like it with dress making patterns, how to thread a sewing machine, all sorts of things, it's like it's in a different language, which of course many sets of instructions are, they start in one language, get translated to another, then the translation gets translated. I'm like it with verbal instructions too, especially when someone explains something three different ways, without checking that I understood the first one, I get really cross as I feel like they've deliberately made something complicated.

Mind you my total cackhandedness is almost legendary, as a friend who saw me trying to insert a coin to release a shopping trolley found, she was just looking at me like I'd come down in the last shower of rain, it was in no way intutitive, but so simple when she showed me, duh!