Favorite special meal for cook-ahead?

Footnotes - in the end, what did you make and how was the menu received?

I'd definitely suggest a braise, as others here did--but instead of a typical roast or stew, which some might be getting a bit tired of by this time of year (or maybe not! long live beouf bourgignon and coq au vin!) might I suggest a Spanish-style seafood braise? A seafood casserole doesn't sound like it's make ahead, but my favorite version, with octopus and squid, definitely is--both of those get lovely and tender with long, slow cooking. I'm trying to find more recipes (try https://honest-food.net/pulpo-gallego-recipe-octopus/), but I don't usually use one. I start out sweating some onions, fennel, carrots, peppers, and garlic in a dutch oven, adding a nice hefty dose of white wine and plum tomatoes, a bit of saffron and smoked paprika, then adding in the squid, sliced into rings, and some baby octopus. Bring to a simmer, put the lid on, then stick it in the oven at 250-300 for about an hour. You can do this the day before, then leave it in the fridge for a day or two. When I'm ready to serve it, I throw a few filets of frozen fish (I like to use hake or halibut, something white and flaky) on top of the stew, replace the lid, and heat it up in the oven for another 30 minutes. In that time, the frozen fish will gently cook as the dish warms. You can even add some shrimp or some scallops a few minutes before serving, if you so desire, again without even needing to thaw--they cook so quickly that the heat from the stew should take care of it in no time. I like to serve it with little individual bowls of lemon wedges and gremolata (grated lemon zest, minced parsley, and ground almonds) that people can sprinkle on their portions, which gives it a wonderful fresh flavor that belies it's stewiness. It feels special and different and fresh, but it really is the ultimate make-ahead. It's also really adaptable to the types of vegetables and braising liquids you have on hand--adding in clam stock, leaving out the saffron if you don't have it, etc. You can also serve it with lots of different things--crusty loaves of bread, creamy polenta, a fresh green salad or peppery watercress, etc. Make a theme of it with a nice charcuterie plate with manchego, jamon serrano, and some marcona almonds and quince jam. And for dessert, a Spanish almond cake (https://food52.com/recipes/22940-tarta-de-santiago-almond-cake) would be a nice touch, or a citrus fruit salad (grapefruit, blood oranges, regular oranges, etc., drizzled with walnut oil and some sweet wine).

Happy Birthday to your dad!

Hope that helps, and happy bi

And what about the birthday boy, if we can use such a phrase?
What's HIS favorite app, main or dessert?

Lasagna! Can be assembled and held in the fridge. Pop it in the oven while enjoying wine and cheese. A big tossed salad (made ahead of time) and crusty Italian bread.

This time of a year, a braise would be perfect, not to mention that it will taste better if made ahead. This beef braised in a whole bottle of Chianti, from Cooks Illustrated, is one of our favorites: https://tinyurl.com/TuscanBeefStew (If having a "stew" is not celebratory enough, just call it "beef braised in wine." It tastes delicious, and is certainly dinner-party worthy. Follow the instructions exactly.)

We like it over polenta, which also can be made ahead, and needs little attention before serving. To make it in the slow cooker (the easiest way, much easier than in the oven): for each 1.5 cups of polenta, whisk in 6 cups of boiling water, 1.5 teaspoons kosher salt and a hunk of butter (about 2 tablespoons). Stir occasionally. On low heat, it will take 3 - 4 hours. Prep a nice green salad in the morning: wash and dry the greens, prep and store in the fridge any other fresh ingredients; toast nuts, make dressing, get the bowl out, put everything in one place, etc. Assemble right before dinner. Easy! ;o)

Especially at this time of year, these are my big favorites for do-ahead dinners that are special: https://food52.com/recipes/13485-rabbit-sinatra-burgundy-style-rabbit-my-way-warning-you-may-also-make-this-with-chicken
https://food52.com/recipes/25918-boeuf-bourguignon

Alexandra Stafford's zucchini involtini on this site is an excellent, delicious make ahead meal. You can add a salad & bread - all easy to do ahead.

Given the cooler weather, I'm partial to braised short ribs and mashed potatoes. Both of which you can make ahead and pop into the oven..