Nutella Cotton Cake

Ingredients:
6 egg yolks
2 whole eggs
100g Nutella
100g cake flour ~ sifted
70g canola oil/vegetable oil
1/8 tsp salt (optional)

6 egg whites
70g caster sugar
1/4 tsp cream tartar

Directions:

1. Place a tray with water on the lowest rack & start preheat oven to 125 deg C.  Line 8" baking pan & grease the side lightly.
2. Heat the oil till warm & remove from heat.  Quick stir in the flour till a smooth paste without any lumps.  Set aside.
3. In another bowl, whisk the egg yolks & eggs till light & pale.  Then add the nutella & continue whisking to combine.
4. Add the flour paste into egg batter with salt & beat to mix well.  Set aside.
5. Beat the egg whites till foamy & add cream tartar.  Then gradually add the sugar & beat till soft peak.
6. Fold 1/3 of meringue into the egg batter gently till all the meringue finish.
7. Pour the batter into the baking pan, bang a few times on the counter top to release the air bubbles trapped in the batter.
8. Low the temp to 120 deg C & bake for 20 mins. (I used fan mode).  After that further lower temp to 110 deg C (I switch to top & bottom) & bake for 90 mins or till cooled.
9. Remove from oven & invert to cool for 5 mins.  Unmould & remove the baking paper.  turn over & let cool completely on cooling rack.