More detailed directions (with pictures)
The important thing to note – all ingredients for the cake need to be at room temperature.
Extract the lemon zest from the lemon. Mix the dry ingredients (flour, baking powder and baking soda) by passing them through a sieve couple of times

Add the eggs to the mixing bowl

Add the erythritol and stevia to the mix.

Mix all ingredients well, until smooth with an electric mixer
Add lemon zest to the mix

Add oil to the mix

Add yogurt to the mix.

Mix all ingredients well, until smooth with an electric mixer
Add the dry ingredients to the mix

Add the cake mix to a springform cake tin

Place the cake tin in a pre-heated oven for 40 to 45 minutes or until toothpick comes out clean.
Allow to cool on the wire rack.
Cut into slices and serve.

