I am beginning to suspect that it is surprisingly common for intelligent, competent adults to somehow make it through the world for a few decades while missing some ordinary skill, like mailing a physical letter, folding a fitted sheet, depositing a check, or reading a bus schedule. Since these tasks are often presented atomically - or, worse, embedded implicitly into other instructions - and it is often possible to get around the need for them, this ignorance is not self-correcting. One can Google "how to deposit a check" and similar phrases, but the sorts of instructions that crop up are often misleading, rely on entangled and potentially similarly-deficient knowledge to be understandable, or are not so much instructions as they are tips and tricks and warnings for people who already know the basic procedure. Asking other people is more effective because they can respond to requests for clarification (and physically pointing at stuff is useful too), but embarrassing, since lacking these skills as an adult is stigmatized. (They are rarely even considered skills by people who have had them for a while.)
This seems like a bad situation. And - if I am correct and gaps like these are common - then it is something of a collective action problem to handle gap-filling without undue social drama. Supposedly, we're good at collective action problems, us rationalists, right? So I propose a thread for the purpose here, with the stipulation that all replies to gap announcements are to be constructive attempts at conveying the relevant procedural knowledge. No asking "how did you manage to be X years old without knowing that?" - if the gap-haver wishes to volunteer the information, that is fine, but asking is to be considered poor form.
(And yes, I have one. It's this: how in the world do people go about the supposedly atomic action of investing in the stock market? Here I am, sitting at my computer, and suppose I want a share of Apple - there isn't a button that says "Buy Our Stock" on their website. There goes my one idea. Where do I go and what do I do there?)
I definitely used to have the same attitude towards cooking, back when my dad and I were first learning to cook. There's a few things I did to alter my perceptions (in no particular order):
Start thinking of cooking as nifty biology/chemistry. There's a lot of books out there that go in-depth on this, but I think my favorite is "On Food and Cooking: The Science and Lore of the Kitchen" (Harold McGee 2004), which covers pretty much every foodstuff I've ever used.
Think of the last time you went out to a nice restaurant to eat, specifically of the best portion of food you got. Imagine being able to eat food of close to this quality multiple times a week, at much lower cost (I generally pay as much to make an 8-serving dish as a restaurant charges for 2). This probably only helps if you're big on food and/or eating fairly low-quality food now, but I found it a big motivator when I was learning.
If you're one of the many people posting in the dating advice comments above, consider the fact that cooking is an attractive skill in a romantic partner, so the time taken to learn it could be a useful investment.
Try starting with recipes you don't need to pay much attention to, such as stews; this helps to minimize the feeling of wasting time, as you just combine the ingredients and leave.
As always, your mileage may vary, especially if you don't think with your stomach like I do.