Start by lining the bottom and sides of the cake pan with parchment paper. Keep aside. Preheat the oven to 180°C.
In a large mixing bowl, combine together butter, milk and yogurt until homogenised.
Empty the cake box into this along with the additional 1/4 cup of flour.
Combine to form a cake batter like consistency using cut and fold method.
Transfer to the prepared pans and bake in the preheated oven of 180°C for 28-35 mins or until a skewer inserted in the centre comes out clean.
Allow it to cool in the pan itself for another 3 to 5 mins and then invert on to a wire rack to cool completely.
Enjoy it plain on its own or layer with any frosting of choice.
Video
Notes
The oven should be preheated to 350 degrees. Very important! It's also important that your cake pan is lined with parchment paper. This will make it much easier when you go to turn the cake out of the pan after baking.
Adding an additional 1/4 cup of flour would help bind the cake batter well making it less crumbly once baked. In short, would give it a little structure that is missing due to a lack of eggs.
Similarly using butter instead of vegetable oil and milk instead of water would elevate the taste of your cake mix.
Always ensure to use room temperature ingredients. It makes mixing the cake batter easier.
Follow the ingredients and instructions mentioned in the cake box you are using. Just substitute the 2 eggs mentioned in the box with 1/2 cup of yogurt to make an eggless cake using cake mix. And remember to add little additional flour.
Add some chocolate chips or crushed nuts to give the cake a nutty flavor.
You can use the same almost magical egg replacement (yogurt) to make an eggless vanilla cake recipe from a boxed cake mix. Just try to use a good quality vanilla extract for optimum flavor. The rest of the recipe remains the same.
If you are using any other box mix than what I have used then the proportions of ingredients might change. Follow the one given in the box. Just make sure to add the additional flour and sub the eggs with yogurt.