This light but satisfying fruit and cornmeal upside-down cake is a dish that can be shopped for at lunchtime and cooked without too much fanfare for dinner. Recipe by Nigella Lawson
One 9-inch square cake (9 to 12 servings)
Vegetable oil for greasing pan
1⅓ cup sugar, divided
3 cups blueberries
2 large eggs
Finely grated zest of 1 large orange
⅔ cup fresh orange juice
⅔ cup olive oil (not extra virgin) or sunflower oil
½ cup regular or instant polenta
1¼ cups all-purpose flour
2 tsp baking powder
½ tsp salt
Heat oven to 350 F.
Grease and line base and sides of a 9-inch-square cake pan with baking parchment, and grease the parchment. Sprinkle ⅓ cup sugar over base of pan, and cover evenly with blueberries.
In a large mixing bowl, combine eggs, 1 cup sugar and orange zest. Whisk until pale and thick. Add orange juice and oil, and whisk until blended. In a separate bowl, whisk together polenta, flour, baking powder and salt. Add flour mixture to egg mixture, whisking until smooth. Pour into prepared pan.
Bake for about 45 to 55 minutes, until golden brown and springy to the touch, and a toothpick inserted near the center comes out clean. Cool cake on a rack for about 5 minutes.
Carefully invert cake onto a serving plate, and slowly peel off parchment paper.
Serve warm or at room temperature.