1 cup unsalted butter (softened, plus extra for buttering the pan)
1 cup plus 2 tablespoons granulated sugar
3 large eggs
1 cup almond flour (ground almonds)
3/4 cup unbleached all-purpose flour (plus extra for dusting the pan)
2/3 cup polenta
2 teaspoons baking powder
1/2 teaspoon salt
  Grated zest and juice of 2 lemons
2 cups Earthbound Farm Frozen Organic Blueberries (still frozen)
3 tablespoons lemon juice
1 cup confectioner's sugar