1 ½ cups / 150gfresh blueberries, washed and dried
For the syrup:
1/3 cup + 2 tbsp/ 100mlwater
1/2 cup / 100gsugar
Juice of 1 lemon
Preheat oven to 360° F/ 180° C. Grease and flour very well a rectangular cake pan.
In a bowl combine flour, baking soda, baking powder and salt and set aside.
In a large bowl beat together the sugar and the olive oil until creamy. Add the eggs, one by one, and continue beating. Add the yogurt and the lemon zest and whisk until homogeneous. Little by little add the dry mixture and whisk until absorbed in the batter. At the end add the blueberries and whisk very carefully with a rubber spatula, until just absorbed.
Pour the batter into the prepared pan. Bake for about 40 minutes or until the cake becomes golden brown on the top and a toothpick inserted in the center comes out without batter (it would probably come out in blueberry juice, but watch out that it doesn't have any liquid yellow batter on it).
Remove the cake from the oven and let it cool for about 1,5 h before adding the syrup.
In a small saucepan over medium heat combine all ingredients. Stir occasionally until the syrup gets almost to the point of simmering (it should not start boiling because the basil taste will become too strong).
Remove the pan from the stove, take out the basil leaves and pour the syrup over the cooled cake in the baking pan. Let the cake cool again about 10-15 minutes and carefully run a knife around its edges. Invert it on a serving plate. Optionally, dust with icing sugar just before serving.