This is all we had left to photograph of this cake. I wasn't even going to put it on after the struggle it gave me whilst making it, but here it is, all over the internet.
First off, this recipe is from Gourmet, but I can't remember the month. I ripped it out of the magazine so I could throw it away, and the picture was on the cover. It looked gorgeous, so any photo I would have taken would have been shamefully inadequate. This one just gives your mouth an idea of what's ahead.
Second, this recipe calls for gelatin. I have never worked with gelatin before. And rarely does something mess up while I am making it that I have to start all over. Except for this one. And the other one from the same day. But never before that. I am going on record that this tasted way better than I expected, and I'd do it again but try to avoid working with gelatin. Not enough experience there to earn a merit badge. It's not like making Jell-O, you know.
You need some down-time with this one, like 4 refrigerating hours, or just make it the night before. You also need an 8 inch springform pan; I did it with a 9 inch and it was a bit thin, but tasted fine.
The worst part is processing the hazelnuts, and even that wasn't that bad. You need some extra, more than the 2 T it calls for. Toast them in a pan until their skins split (really split), then dump them on a towel and rub off the skins. Yes, the list of ingredients and directions takes up quite a lot of space, but, gelatin aside, it moved along really quickly.
Chocolate-Glazed Hazelnut Mousse Cake
For Shortbread Base:
2 T hazelnuts, toasted and skins rubbed off
3 T sugar
1/2 c all-purpose flour
1/2 stick unsalted butter, softened
2 T unsweetened Dutch-process cocoa
1/8 t salt
For Mousse:
1 t unflavored gelatin (1/4 oz envelope) OR NOT
3 T cold water
1/2 c Nutella
1/2 c mascarpone (1/4 lb)
1 1/2 c chilled heavy cream
2 T unsweetened cocoa
3 T sugar
For Ganache:
1/4 c plus 1 T heavy cream
3 1/2 oz good quality bittersweet chocolate (not unsweetened)
Make shortbread base: Put oven rack in middle position and preheat to 350 F. Lock the springform pan sides to the base, and line with a round of parchment paper. Pulse hazelnuts and sugar in a food processor till finely chopped, then add flour, butter, cocoa and salt and pulse just until a dough forms.
Press dough evenly in springform pan with your fingers. Prick all over with a fork and bake until just dry to the touch, about 18-20 minutes. Transfer to a cooling rack for 30 minutes. Remove sides of pan and carefully slide out the parchment paper from underneath., then reattach the sides of pan around the shortbread base.
Make Mousse (while shortbread is cooling): Sprinkle gelatin over the water in a small saucepan and let stand about 5 minutes until softened. Heat gelatin over low heat, stirring, just until gelatin is melted, about 2 minutes. Whisk in Nutella until combined and remove from heat.
In another bowl, whisk together the mascarpone and Nutella mixture until combined. In a standing mixer, whip the cream, cocoa powder and sugar on low speed until combined, then on high speed until soft peaks form. Whisk a third of this cream into the mascarpone/Nutella mixture to lighten, then fold in remaining cream. Spoon on shortbread base in pan, gently smoothing top, then chill, covered, at least 3 hours.
Make Ganache: Bring cream to a simmer in a small heavy saucepan and remove from heat. Add chopped chocolate and let stand one minute. Stir till combined and smooth. Cool, if necessary, to thicken, but make sure it is still pourable.
Run a warm knife around springform pan sides to loosen the cake, then remove sides and slide cake on a serving plate. Pour ganache over the top, letting it run down the sides.
Note: Cake can be made without glaze and kept chilled up to 2 days. Cake can be glazed 6 hours ahead and chilled, uncovered.