Place the blanched almonds and sugar in a food processor and pulse until finely ground, but not too powdery.

Transfer the mixture to a bowl and add the cold butter cubes, cornmeal, all-purpose flour, and a pinch of salt. Mix quickly with your hands, rubbing the ingredients together just enough to combine without warming the dough.

The mixture should be crumbly and sandy, not smooth or compact.

In a small bowl, mix the egg yolks with the grated lemon zest and the vanilla seeds. Add this mixture to the dough and gently combine, always keeping the texture crumbly.

Lightly butter a 11-inch (28 cm) round cake pan. Crumble the dough evenly into the pan without pressing it down.

Sprinkle the surface evenly with the sugar and scatter the whole almonds on top.

Bake in a preheated oven at 350°F (180°C) for about 50 minutes, until golden.

Let the cake cool completely before serving.