-
1
Preheat the oven to 350.
-
2
Butter an 8-inch-square baking pan and line the bottom with wax paper or parchment.
-
3
In a food processor, finely grind 1 cup of the walnuts with 1/4 cup of the granulated sugar and 1/2 teaspoon of salt.
-
4
In a medium bowl, using an electric mixer, beat 4 tablespoons of the butter with the remaining 3/4 cup of granulated sugar until pale and fluffy.
-
5
Beat in the egg yolks, 1 at a time, making sure each is incorporated before adding the next.
-
6
Stir in the ground walnuts.
-
7
Beat the egg whites with a pinch of salt until stiff peaks form.
-
8
Gently fold the beaten whites into the walnut batter, then pour into the prepared pan.
-
9
Tilt the pan to evenly distribute the batter.
-
10
Bake for about 40 minutes, or until the cake is set and begins to pull away from the side of the pan.
-
11
Transfer to a rack and let cool for 10 minutes.
-
12
Run a knife around the side of the pan and turn the cake out onto a serving plate to cool completely.
-
13
In a food processor, pulse the remaining 1 cup of walnuts with the confectioners' sugar until finely ground.
-
14
Add the remaining 4 tablespoons of butter and pulse until creamy.
-
15
Spread the frosting evenly over the cake.
-
16
Using the edge of a tablespoon, make a decorative pattern in the frosting.
-
17
Cut the cake into 1-by-2-inch bars and serve.
