Preheat the oven to 350° F.
Grease 8x½-inch or 9-inch loaf pan with nonstick spray or butter. Set aside.
In a large mixing bowl, take flour, baking powder, and salt.
Whisk for few seconds to combine well.
Add chocolate chips into the flour mixture and mix well.
In a medium bowl, add oil, melted butter, sour cream, sugar, and vanilla.
Stir well until everything is combined and becomes a smooth mixture.
In to dry ingredients, add the wet mixture and ½ cup of milk.
Mix everything gently until just combined, and there is no visible flour. Do not overmix.
Pour the batter into a prepared loaf pan.
Bake the chocolate chip cake in a preheated oven for 45-55 minutes or until a wooden skewer or a cake tester inserted into the center comes out clean.
Keep an eye on the cake. If the top of the loaf cake is browning too quickly, remove it from the oven after 30 - 35 minutes and loosely cover it with aluminum foil. Return it to the oven and continue baking for the remaining time.
Remove the loaf cake from the oven and transfer the loaf pan onto a wire rack. Allow the cake to cool completely into the pan.
Once the chocolate chip cake is cooled, remove it from the pan, slice, and serve.