Apologies for the wall of text. Posting this is somewhat cathartic.
My biggest concern is the quantities I'm making. I have a 14-pound boneless ribeye roast, 12 pounds of Yukon Golds to mash, 8 pounds of carrots, and 4 pounds of haricots verts. (Haha, this was mostly accidental, but there is a direct correlation between the weight of the ingredient I bought and how popular I expect it to be among my wife's enormous Irish Catholic family.) Oh, and six romaine hearts plus two 5-ounce tubs of assorted other greens. I'm serving somewhere between 14 and 19 people, excluding children and vegetarians. Here's the plan.
The roast is trimmed and pre-salted (maybe too trimmed; it started at 20 pounds) with 7 teaspoons of DC kosher salt. It's wrapped in plastic now, but I'm going to unwrap it and let it dry out starting on Christmas Eve. I also want to tie it up so it cooks evenly. It's too big for any roasting pan I could find, so I'm cooking it on a half-sheet pan with a wire rack. The plan is low and slow at 200ºF until it reaches 125º, followed by a sear at 550º. The sheet pan is too shallow to hold any water, so I'll have a bed of salt underneath to catch the drippings and keep them from smoking. Big problem here is timing—Serious Eats says the size of the roast doesn't matter, and it'll take 3-4 hours to come to temp, but commenters say their large roasts took six hours. I'm going to take it out of the fridge at 8 am, put it in the oven at 10, and hope it's ready for dinner at around 4.
The day before, I'll use some of the beef trimmings, some brown sauce, and some wine to make a gravy on the stovetop.
Next is the mashed potatoes. Twelve pounds is a lot of goddamn potatoes, and I'm not really sure how I want to cook them. For simplicity's sake I just want to use a big lobster pot or something, but that's a lot of water to boil. Since they're going to heat so slowly, I wonder if I should just boil them whole. My concern with quartering them like I normally do is that these little bits of potato are going to be sitting in slowly-heating tepid water for much longer than they normally would. But whatever happens, I'll run them through a food mill then mix in four pounds of butter and enough milk to get them to the right consistency. (Now that I think about it, this is really too much... Everyone gets leftovers, I guess.)
The carrots I'm going to braise with butter, water, sugar, salt, and pepper. Maybe garlic, I don't know. I'll peel and slice them the night before and hope they fit into my 10" deep sauté pan. If not, I'll put them in a Dutch oven. I'll keep topping them off with water, and when they're almost cooked through, I'll let the water boil off and caramelize them a bit.
And finally, the green beans. I'll blanch them the night before, then toss in a skillet with some shallots, butter, and olive oil.
Oh, jesus, and the salad, uh, that's going to be a plain old vinaigrette. No idea how much to make, but I'll have some gloppy bottled shit to pick up the slack, because I expect fully half of the people to see the vinaigrette, shrug, and reach for something more familiar. (If it were up to me, I'd dress the salad beforehand and serve it as a course, but it is not up to me.)
Haha, oh, and dinner rolls, my god. Uh, while the meat is resting and the oven is coming up to 550, I'll throw those in. They're frozen and very forgiving.
And if I fuck it all up, we'll order Chinese!