Well, Cook's Illustrated's Dark Chocolate Mousse is THE best - very deep chocolatey and decadent....
I don't know if you're looking for a chocolate cake recipe, but I have 10 -12 T&T, both with flour and flourless. One of them is the Mexican Chocolate Icebox Cake - don't know whether you've tried this or not, but it's amazing, plus looks beautiful - I've made it many times.
Here are some others out of the 10-12:
Devil's Food Cake with Fluffy White Frosting from Chocolatier/Godiva)
Chocolate Rhapsody (I'm doing this one for Thanksgiving - it's a real PITA to make, and I've had to modify it a lot from the original, but it's excellent)
Chocolate Espresso Torte (Fine Cooking)
Chocolate Sour Cream Bundt Cake from Cook's Illustrated - I LOVE this one!!!
I also have a dark chocolate cheesecake recipe. Let me know.
If you have an ice cream maker, Dorie Greenspan's Chocolate Ganache Ice Cream is fantastic.
Another recipe to consider is Chocolate Rum Dessert, a mousse type recipe- not T&T, but has had great reviews, plus I posted it a long time ago for LuisaCalif, and she loved it.
So many more - too many to list - Maybe if you narrow it down a bit?