Today is the third edition of the one and only collaborative food blogging event, otherwise known as "Is My Blog Burning?". The first edition, hosted by Alberto, was all about soup. The second edition, hosted by yours truly, had a tartine theme.

Today's event is hosted by the lovely Singaporean foodie, Renée, and the theme is Cake Walk. As Renée explains, a cake walk is a sort of lottery organized at local fun fairs, in which the prizes are cakes baked and donated by people from the community. I knew about fund-raising bake sales, but I'd never heard of that concept. It sure sounds great : gambling and cakes, it doesn't get any better than that!

I scratched my head and pondered the possibilities for quite a while : the world of cakes is vast -- and beautiful I might add -- so a lot of room was left for personal inspiration. I had settled on an idea, but at the very last minute, as is often the case, inspiration came knocking on my door again : what could be more fitting a contribution than a Chocolate & Zucchini Cake?

Apparently, in the Midwest, zucchini plants seem to grow with supernatural vigor. When harvest season comes around, people are overloaded with their crop, and have developped all kinds of inventive ways to use it up. Someone even told me that nobody ever locked their cars in his small town, except when it's zucchini season, otherwise you risk coming back to find that someone has left a crate of zucchini on the passenger seat! One of the popular uses of extra zucchini (apart from abandoning it on the steps of the church) is in breads and cakes, including chocolate and zucchini cakes.

When I picked the name for this blog, I wasn't at all referring to this (see About for the real explanation), but over time I've had a few emails from readers telling me about this type of cake, and even requests for recipe recommendation. Well, I have one now!

I searched the web for recipes, found several, selected the ones that made the most sense, read the bakers' comments and variation ideas, blended all this thoroughly with a spatula, and ended up with this version.

I baked it yesterday afternoon, and served it in the evening to my favorite taste-testers, Ludo, Marie-Laure, Stéphan and Patricia, who had come around for dinner (more on that in the coming days of course). And boy, was it scrumptious! When I started cutting slices, I could tell immediately that the texture was just right, fluffy and moist, with a slightly crispy outer crust. The big advantage of using grated zucchini is that it provides some of this moistness, allowing you to reduce the amount of butter : one stick for a cake this big isn't much. There is no way anyone can taste the zucchini in there, the only giveaway is that you can sometimes spot a little filament when you cut a bite.

A lot of recipes called for walnuts or pecans, mixed in with the batter or added on top, but I think hazelnuts and chocolate make a very happy couple, which is why I used them to top the cake. We all enjoyed the toasted nutty crunch it provided, but you could omit them or sub your favorite kind of nut.

In addition to being a deep and beautiful shade of brown, the cake has a voluptuous chocolate flavor. We can thank the cocoa powder and the chocolate chips for that (actually, pardon me, I use ganache drops, bought in bulk at G.Detou), and also the dash of coffee granules. The latter is a good trick (passed on to me by my grandmother, I kid you not) to remember when working with chocolate : you can't discern the coffee as such, but it brings out the chocolate taste even further.

Chocolate & Zucchini Cake

- 1 1/2 C (180 g) all-purpose flour
- 1/2 C (60 g) whole wheat flour (of course, you can just use 2 C / 240 g all-purpose flour, I was just trying to be good)
- 1/2 C (40 g) unsweetened cocoa powder
- 1 tsp baking soda
- 1/2 tsp baking powder
- 1/2 tsp salt
- 1/2 C (110 g) butter, softened
- 1 C (160 g) light brown sugar
- 1 tsp vanilla extract
- 1 tsp instant coffee granules (the Nescafé type, the stronger the better)
- 3 eggs, at room temperature
- 2 C zucchini, unpeeled, grated (about 280 g, two medium)
- 1 C (170 g) chocolate chips

Topping :
- 40 g light brown sugar
- 1/2 C (70 g) hazelnuts, toasted and chopped

(Serves 10.)

Preheat the oven to 180°C (360°F). Grease a 3 quart (3 L) springform cake pan, and flour it or sprinkle with cocoa powder : this is to help the cake unmold easily, especially if you're not using a magic non-stick pan.

In a large bowl, whisk together the flours, cocoa powder, baking soda, baking powder and salt.

In your food processor, combine the sugar and butter, and mix until fluffy. Add in the vanilla extract and espresso powder, then the eggs, one at a time, mixing thoroughly between each addition.

Spoon in the flour mixture, reserving the last half-cup of it. Mix thoroughly, the batter will be thick.

Add the grated zucchini and the chocolate chips to the reserved flour mixture, and toss to coat. Fold in the batter, and blend thoroughly, it's fun. Pour into the prepared cake pan, and flatten the surface with a spatula.

In a small bowl, combine the topping ingredients, and sprinkle all over the batter. Bake for 40 to 50 minutes, until a cake tester comes out clean. Turn out on a rack to cool for half an hour, then unmold.