1In a large bowl, combine the egg, milk, vanilla and oil. Beat until well mixed.
In another separate bowl, sift the flour, baking powder and sugar.
2Add the dry ingredients to the wet ingredients.
Fold gently with a wooden or rubber spoon until just combined. Mix only until a smooth batter forms (a couple of lumps are OK).
3Spoon one third of the cake batter into the bottom of the loaf pan. With a spoon, add three parallel lines of Nutella along the length of the pan – start with one line in the center of the pan, and then one along each side of that center line. Drag a skewer across the three tracks of Nutella (see photo).
4Spoon half of the remaining cake batter ontop of the first layer in the pan. Again, with a spoon, add three parallel lines of Nutella as before and drag a skewer across the three tracks of Nutella.
5Repeat with remaining batter and Nutella.
Bake for approx 40 mins. Perform a skewer test. Remember, you are testing to see whether the cake itself is cooked – the Nutella will remain molten while warm. Look for white cake crumbs to test the “done-ness” of the cake.
6Allow to cool for 10 minutes and remove from pan.