In a large bowl, mix the room temperature milk and vinegar and let it sit for 5 minutes or till curdles.
In a separate bowl, sift the flour, baking powder, baking soda, and salt well. Sifting will distribute the leavening agents well. Weigh all the ingredients using a weighing scale for perfect results.
In the buttermilk bowl, add the sugar, oil and vanilla essence. Whisk well till the sugar almost dissolves.
Add the sifted Dry ingredients to the wet Ingredients in three small batches gently whisking till combined. Ensure no lumps remain.
The batter should be smooth and flowing not too thick nor runny. If batter looks too thick you can add 1-2 tablespoon of milk.
Bake in a preheated oven @170C for 40-45 mins or till a toothpick inserted in the center comes out clean. It took 45mins for me. Let it cool in the pan for 15-20 mins then remove it to cool completely on a wire rack.