Looking for project recipes

I'm looking for project recipes - recipes that require a substantial amount of time and/or work, that fill up your whole day or that you chip away at over the course of the week. (And that reward you for your labour accordingly!)

Some examples: I've made the Mushroom Wellington a few times for Christmas dinner, and made Claire's croissants earlier this year to rapturous success. They both require work and planning and reward you for it.

NYT has a filter for "Under one hour" and "Easy", but I haven't found a good way to filter for "Hard" or "Multiple hours"!

Doe anyone have any good recommendations?

Bonus points if they freeze well!