Take a mixing bowl to add flour, baking soda, baking powder, and salt. Mix it until well combined and set it aside.
Take a mixing bowl to add sugar, vegetable oil, and butter mix them with a whisker or with an electric mixture. Mix them until it becomes fluffy and creamy. After that add the egg, milk, sour cream, and vanilla essence into the mixture and mix them well.
Now, add the dry ingredients and mix them well until there are no lumps remaining.
Preheat your air fryer at 160C/320F for 2 minutes.
Prepare your cake pan by brushing some butter or placing parchment paper underneath the pan.
Pour the batter into the pan and tap out the air from the batter if there is some.
Place the cake pan in the air fryer basket (be careful with the basket cause it’s hot) and cook at 160C/320F for 30 minutes.
Insert a clean toothpick into the center of the cake and if it comes out clean, the cake is cooked. If there are some cake lumps remaining when pulling out the toothpick. Cook for 2-3 minutes more and check if it's done cooking.
Let the cake cool for about 15-20 minutes in the pan. Then remove it from the pan and let it cool completely.
Spread your favorite jam or decorate if you like and serve. Or you can simply slice the cake and serve with a hot cup of coffee or milk.