First, make the raspberry spread. Put the ingredients needed in a small saucepan and cook until it reduced to a thick, jam-like spread. Let it cool, the discard the cinnamon stick.
Preheat the oven to 170°C.
In a large mixing bowl beat the eggs and sugar until creamy, then stir in the vanilla extract and oil.
Sift and fold in the flour and bicarb then the ground almonds and stir gently until combined.
Line a rectangular baking tray with parchment paper. Spoon the mixture into the tray, spread it out evenly.
Spread the raspberry sauce on top evenly, then scatter the almond flakes on top.
Cut the nectarines into thin wedges and arrange these on top of spread and almonds. Scatter some sugar on top.
Bake for about 45-55 minutes until golden or until an inserted skewer in the middle comes out clean. You might need to cover it with foil after 20-30 minutes of baking if the top is too brown.
Turn off the oven, open the door and let the cake rest for five minutes, then move it to a wire rack and let it cool completely.
When completely cooled, slice it into squares and sprinkle with icing sugar.