Gateau Lyonnais (Chocolate Chestnut Cake)
When I Google “gateau lyonnais”, the results do not yield a chocolate chestnut. This recipe is one that my mother used to make and since I love all recipes with chestnuts, it has always been one of my favorite cakes for the winter. It turns out that my children also adore this cake, I think because it is less traditional chocolate cake and more like a chocolate mousse. It is also flourless, so a great gluten-free recipe! I used to only make this once a year or so but now find that I make it more regularly since it is so popular among my family members and yet still so simple to make. Beware this is a very rich cake, no ice cream on the side needed.
Yield: 10-12 servings
Active Cooking Time: 20-30 mimnutes
Ingredients:
Cake
3 oz semi-sweet chocolate, chopped
4 eggs, separated
3/4 cup sugar
7 oz canned, unsweetened, chestnut purée
Frosting
5 oz. semi-sweet chocolate, chopped
2 tbs water
2 egg yolks
1/2 cup heavy cream
1 tbs sugar
1/2 tbs rum, or to taste (optional)
Beat chestnut purée with egg yolks and half of the sugar, until thick and light. Set aside in a separate bowl. 
Beat egg whites with remaining half of sugar. 
Add one quarter of egg whites into chestnut mixture. 
Add melted chocolate into chestnut mixture. 
Add chocolate chestnut mixture to remaining egg whites. Carefully fold until no more egg whites can be seen. 
The last step to this cake is to frost it with the chocolate ganache. It’s best to wait till the cake has cooled completely, then spread a generous amount of ganache all around.
Note: The cake will not be too high as a traditional sponge cake, but the richness will make up for its size.