Firstly sieve the all purpose flour and baking powder a couple of times. Set aside until use.
In a deep bowl, add the melted butter, oil and sugar and beat using a hand blender/ stand mixer/ a whisk for a couple of mins until the sugar is completely mixed in.
Continue whisking, adding one egg at a time, once all the eggs are whisked in beat this mixture until it's pale yellow in color.
Next add the vanilla and milk, beat until it's combined well. Next stir in the sifted flour and baking powder, mix gradually and whisk until combined. Now stir in the chocolate chips and mix.
Meanwhile grease a loaf tin with butter and dust it with flour. Now pour the batter into a greased pan, sprinkle few chocolate chips over the top too.
Bake this in a preheated oven at 180°c or 350° f for 40 to 45 mins or until a skewer inserted comes out clean. Once baked perfectly remove and cool at the room temperature for atleast 30 mins. Later slice and serve.