Preheat oven to 350 F or 180 C and line a 20 cm baking pan with parchment paper.
In a bowl, sieve the flour, baking powder and bicarbonate of soda. Then in a separate bowl, add the remaining ingredients and mix until combined. Fold in the flour to the wet mix. Do not over mix as this will cause the cake to become tough.
Add the batter to the baking pan and place in the oven for about 25 - 30 minutes or until the top is set and the middle has a slight wobble.
Remove from the oven and allow to cool in the baking pan for 10 minutes, then turn out on to a cooling rack.