Preheat oven to 160 °C (320°F) with the fan on (see note 2 if you don't have a fan function) and grease and/or line two 8 inch cake tins (I use my homemade cake release).
Sift together flour, baking powder and salt. Mix together using a whisk and set aside.
In a large mixing bowl, combine yoghurt, sugar, vanilla and baking soda. Mix until well combined and set aside.
In a microwave safe bowl or jug, combine butter, oil and milk. Heat in the microwave (you can do this over a stovetop if you prefer), until the butter is fully melted and the mixture is hot to the touch.
By this point your yoghurt/baking soda mixture should be frothy. To it add in half of the heated milk mixture and using a whisk mix until combined. Then add in half of your pre-sifted dry ingredients and gently mix with the whisk until just combined. Then add in the remaining milk mixture and gently whisk until just combined. Finish by adding the remaining dry ingredients and gently whisk until just combined. Do not overmix.
Distribute the batter evenly into the two 8 inch cake tins, and then give the cake tins a light bang on the counter to release any large air bubbles.
Bake for 28 minutes, or until a toothpick comes out clean. Let the cakes cool in the cake tins for about 20 minutes, before turning them out onto a wire rack to completely cool.
