Orange-Scented Walnut Cake

For the month of February, I have decided to cook recipes from the cookbook Bitter by Jennifer McLagan.  I was interested to see what fruits and vegetables she called bitter.  Some are more bitter than others and she talks a lot about how bitter has been bred out of many foods, but in reality we only need a little bit of bitter to start our appetites.  I am not quite done reading this book yet, but here is a recipe adapted from the cookbook.

The thing I find ironic is that I never thought that I liked bitter foods, but after reading the cookbook I have found that many of the contrasts that I like to eat are bitter foods (maybe only subtlety bitter).  For example, I tried grapefruit again last year and this time I didn't find it very bitter.  Of course I tried the pink or red variety which much of the bitter has been bred out.  I, however, love arugula.  I discovered this lettuce more than 10 years ago when I lived in Germany.  I tried it once and ever since I have looked for it.  It is one of my favorite topping on pizza (not wilted, but added after baking).  One other bitter food that I have come to love (also while I lived in Germany) is Brussel sprouts.  Of course, roasting them with oil and balsamic vinegar brings out the sweetness of the vegetable so many people have come to eat them in this manner.  So join me in my journey in trying bitter foods this month.

This walnut cake is moist and not very sweet.

Orange-Scented Walnut Cake
6 ounces walnut pieces
2 slices wheat or other oat bread
5.5 ounces unsalted butter
2/3 cup sugar
4 eggs, separated
1 teaspoon cardamom
pinch of salt
2 small oranges, zested (with a little of the pith)
pinch cream of tartar
cocoa powder to dust the top

Preheat the oven to 350 F.  Butter a 9 inch springform pan.  Then cut a round of parchment to line the bottom.  (The butter helps it stick as well as greases the edges.)   Spread the walnuts and 2 slices of bread on a baking sheet and bake for about 10 minutes.  Check after about 5 minutes and flip the bread if it is starting to dry on one side.  The nuts should be lightly toasted and you should be able to smell them.  Remove from oven and let them cool.   Reduce the temperature on the oven to 325 F.

Put the butter in a stand mixer with paddle attachment.  Set aside 3 tablespoons of the sugar and add the rest to the butter.  Cream the butter and sugar until light and fluffy.

Add the toasted bread and walnuts to a food processor and pulse until finely ground (as this will be the flour for the recipe).

Add the egg yolks, one at a time with beating in between each addition, to the creamed butter and sugar mixture.  Stir in the ground walnuts and bread mixture.  Add the cardamom and salt.  Finely grate the zest of the orange including a little of the pith.  (You can juice the orange and drink it or use the juice in another recipe.)

In a clean bowl, whisk the egg whites until frothy.  Add the cream of tartar and continue to whisk until white.  Add the reserved three tablespoons of sugar, one at a time, whisking in between to incorporate.  Add a large spoonful or two to the butter/walnut mixture.  Tip the batter into the egg whites and fold until mixed.  Pour the batter into the prepared pan and smooth the top.  Bake for aout 45 minutes or until golden and a toothpick inserted in the center comes out clean.

Let the cake cool for 5 minutes and then release from the springform pan.  Let cool completely and dust with cocoa powder.  This cake improves with some time and is better if you can wait a day before eating.  It also goes good with coffee (per my coworkers testimonies).