But you can absolutely use flour in hot drippings. Hot water, no... but hot fat? Definitely. In fact that's exactly how you should do it.

Some canned goods are nearly indistinguishable from fresh. Pumpkin is definitely in that class. Green beans are not. Corn is. Cranberry sauce... well, that depends on what you want. I like a fancy fresh cranberry sauce made with walnuts and apple. I know lots of people who like the gelatin that comes in a can. I consider them two different foods entirely though. I know plenty of people who serve both at their dinners.

Gravy is such a critically important part is holiday dinner though, screwing it up can ruin the whole meal.

If you don't know how to make it, definitely learn, but do so well before the day of the dinner. You also have to appreciate how the flavors you add to the turkey affect the drippings and subsequently the gravy. Wrapping a bird in bacon might give it a richer flavor but it makes for awful gravy from the drippings.

There's a lot that can go wrong if you don't know what you're doing, though. So if that's the case, canned gravy can work. It won't be amazing, it won't win any awards, but if the rest of the food is en pointe, it'll perform well.

Still... if you're gonna claim to know how to cook a turkey and not know shit about gravy, then I think you should probably let someone else handle the whole thing.

You shouldn't need water...

You make a roux with the drippings and flour, no water at all. The best way to make an amazing gravy is to flavor the drippings. Cut up a bunch of onions, parsnips, carrots, celery and done garlic, all of that goes in the roasting pan under the turkey. Then put a cup or so of broth in there, that will keep the drippings from burning off.

At the end, just filter out the cooked veggies (they're going to be overcooked and useless, I just toss them) and let the liquid drippings sit for 15-30 minutes, fat will rise and you can skim it off. Measure it out and mix it up in a sauce pan with equal amounts flour over medium heat. Stir and cook for 5-10 minutes, then mix it into the remaining drippings and another couple of cups of broth(I measure with my heart here). Heat it up to around 170-180 and it should thicken, add more broth if it's too thick.

Season with a little salt and a lotta pepper.

No water needed at any point.