Combine the almonds, flour, baking powder, and salt in an electric food processor and process until the almonds are finely chopped. I often retain ahandful of almonds to sprinkle on top as the cake goes in the overn.
8 oz unblanched almonds, 1 1/2 cups all-purpose flour, 2 tsp baking powder, 1 pinch kosher salt
Transfer the mixture to a mixing bowl.
Beat the butter and sugar together until light and fluffy.
12 tbsp butter, 3/4 cup sugar
Add the egg yolks and beat until thoroughly combined.
4 large eggs
Add the butter mixture to the almond mixture and mix thoroughly with a wooden spoon.
Beat the egg whites until they form stiff peaks and fold into the batter with a rubber spatula.
Smear the batter into a greased and floured 9-inch (23 cm) spring form pan and bake in a preheated 350F (180C) oven until a toothpick inserted in the centre comes out clean, about 45 minutes. Add the reserved almonds liberally on top.