¼ C semolina, plus more for the plan
- Butter a 9-inch cake pan. Line with a 9 inch round of parchment paper. Butter the paper. Dust the pan with the extra semolina, shaking out excess. Put the pan in the fridge to set the coating while you’re making the batter.
- Put toasted, skinned hazelnuts in the bowl of a food processor and pulse until finely chopped.
- In a small bowl, combine the cake flour, remaining semolina, baking powder and salt.
- Put the remaining butter and the brown sugar in the bowl of an electric mixer and cream together for a few minutes. Add the eggs one at a time, beating thoroughly before adding the next egg. Scrape down the bowl. Add the hazelnuts and beat briefly to combine.
- Remove bowl from mixer then add dry ingredients, folding together gently with rubber spatula. Fold in vanilla extract and olive oil, then scrape into prepared cake pan.