Torta Sbrisolona is a traditional crumbly almond cake from Mantua. Made with wheat flour, fine cornmeal, butter, almonds, sugar, egg yolks, and lemon zest, it is traditionally broken into irregular pieces rather than cut into neat slices.
Preheat the oven to 350°F (175°C).
Lightly butter a 10-inch round cake pan.
Set aside approximately 12 whole almonds for the top.
Do not knead or compress the mixture; its coarse, crumbly texture is the defining feature of Sbrisolona. Use finely ground cornmeal rather than coarse polenta meal, and allow the cake to cool completely so it becomes crisp and breaks cleanly.
Coarsely chop the remaining almonds, leaving a mixture of small and larger pieces.
Combine the all-purpose flour, cornmeal, sugar, chopped almonds, lemon zest, and salt in a large bowl.
Add the cold butter.
Rub the butter into the dry ingredients with your fingertips until the mixture forms coarse, uneven crumbs.
Add the egg yolks.
Mix gently with your fingertips until the yolks are distributed, keeping the dough loose and crumbly rather than forming a smooth ball.
Scatter the mixture loosely into the prepared pan.
Level it gently without pressing or compacting the crumbs.
Arrange the reserved whole almonds over the surface.
Bake for 40 to 45 minutes, until deeply golden and crisp.
Let the cake cool completely in the pan.
Remove it carefully and serve by breaking it into irregular pieces with your hands.
