Preheat the oven to 170 Celsius - 338 Fahrenheit
Grease a 20 cm diameter pan well. Cut baking paper into a circle of the pan's size and place it on the bottom.
Sift flour into a large, deep bowl, add baking powder, baking soda and salt, add chocolate chips and mix well.
In a separate bowl, mix orange juice, water, sugar, oil, orange zest and vanilla extract.
Add the wet mixture to the flour mixture and mix until combined.
Pour the batter into the greased pan and level with a spatula.
Bake in the center of the oven for 40-45 minutes until a toothpick or wooden skewer comes out clean.
Remove from the oven and place on a wire rack to cool completely, before removing the cake from the pan.
