Prepare a 8x8 or 9x9 inch microwave safe dish. Brush the sides with oil and place a parchment paper at the bottom.
In a large bowl, sift the dry ingredients-----all purpose flour, baking soda, baking flour, salt.
Using a whisk, whisk the dry ingredients well and keep aside.
In another bowl, add the remaining ingredients---- oil, milk, yogurt, vanilla essence, vinegar and sugar.
Mix very well until all the sugar dissolves.
Then add the wet ingredients to the dry ingredients and mix using a spatula. DO NOT OVERMIX.
Pour the batter into the microwave safe dish. Give it a few taps on the counter to get rid of air bubbles.
Now microwave it at high power (100%) for 10 minutes.
Once done insert a toothpick in the center. If it comes out clean, it is done. If it comes out wet, give it 1-2 minutes more.
Using oven mitts, carefully remove the dish (it will be very hot!) and allow it to cool completely before cutting into it.