Pre-heat the oven for 5 mins.
Add 2-3 tablespoon of apple cider vinegar to lukewarm milk to make a frothy buttermilk.
Sift the dry ingredients in a bowl.Keep it aside.
Add the butter milk to above dry ingredients and mix well.
Once they start combining, add oil and whisk in the mixer until it comes together as a batter. It should be pouring consistency. If you feel it is too thick, add few spoons of milk and whisk again.
Pour the batter evenly in a cup cake liner and give it a tap to adjust the batter evenly in the muffin tray.
Bake the muffins for 10 mins and take them out.
Now, garnish them with chocolate chips and bake them for 20-25 mins or until toothpick comes clean. Ensure they are more in the middle and not side as the chips will melt and overflow if they are on a side once you bake again.
Let it rest for 10-15 mins before you serve. Enjoy with a cup of coffee or whipped cream as per choice.