“ohhhhh why do recipes always underestimate how long it takes to cook something” this is not a problem that you need to have with any given recipe more than once.
it’s very normal for a dish to take you longer to make than the recipe suggests. the recipe was probably developed by people who have cooked more than you have & can do things quicker—and also a lot of them cheat imo by putting eg “chopped onions” in the ingredients list & thus not counting the time it takes to chop onions
that being said, if you regularly find that recipes are taking you longer to make than the recipe says they will, you can time yourself cooking the recipe, & then write that time down.
usually the first time you cook something it will take longer than it ever takes again, so the first time, i would recommend writing it on a post it note & sticking it in there. that will give you kind of a ceiling for how long it will take to make it again. then the next time you make the dish, if it’s worth making again, you can see how long it takes & write that number down in the cookbook directly (unless you really like post it notes).
the same thing goes for servings. most cookbooks err on the side of assuming people will eat really big servings—it’s good to know how much a recipe actually yielded for your household. especially if you’re cooking for a mix of ages (little kids eat less, teenagers eat more, old people eat less) or cooking for someone who’s bulking or something
same thing goes for variations. if you halved it & it worked, write that down! different kind of cheese? make a note of it! if it worked, write it down. also if it didn’t work but you suspect that you’ll forget it didn’t work & be tempted to do it again—write that down
for online recipes i tend to do all this in the comments. i know, i know. a lot of times i’m that stereotypical person from that toast article who’s like “I love this recipe! I added garlic powder, Italian seasoning, a few flakes of nutritional yeast, half a bottle of kombucha, za’atar, dried onion, and biscuit mix to mine. Great idea!” i don’t really get why that kind of thing seems to make people so mad…to me that kind of information about whether variations worked or not, is always useful
that being said i am starting to get scared of losing some of my favorite recipes to linkrot or losing my notes on a recipe to the website switching their commenting section host. i gotta print that stuff out & put it in a binder!!!!
Paprika is great for this!! Can import a recipe from a URL and then edit everything from there, along with adding additional notes. Slightly annoying to keep it up to date but invaluable when building your own repertoire.