I've been veg for 20 years, so have been around the block, but would love any suggestions for something decadent and lovely. This will accompany a traditional Xmas dinner spread (stuffing, mashed potatoes, green beans, rolls, turkey, etc.) at my parents' house and be an additional course for 4 vegetarians and 2 carnivores. Two of the four are my kids, but they are relatively adventurous and also we don't really worry that much about them anyway--there will be plenty on the table.
In the past I've done spanakopita and butternut squash lasagna. Something with a tart crust or some other lovely buttery substrate is always nice. ;) Calories no concern. Not looking to go vegan here--we eat dairy and eggs. No pasta maker at that house, or I'd do a fresh ravioli.
I am a very experienced cook and pretty willing to tackle anything. This is also a nice time for something with pricey ingredients that I might not normally spring for.