Preheat the oven to 160°C.
Arrange mini cake cups on a baking tray.
Using a sieve, sift flour, cocoa powder, baking powder, baking soda and salt into a bowl.
In another mixing bowl, add beetroot puree, yogurt, sugar, vanilla and oil.
Whisk them together.
Add the dry ingredient mixture.
Whisk till the flour mixture is incorporated into the wet mixture. Don't over mix.
Using two teaspoons, fill the mini cups with the batter, ¾ of the way.
Bake the mini muffins for 10 minutes.
Insert a toothpick in the middle of one muffin. If it comes out clean then the muffins are ready.
Take the tray out of the oven. Allow th muffins to cool down completely.