Preheat oven to 375°F (190°C).
In a large bowl, whisk together the flour, cocoa powder, baking powder, baking soda, and salt.
In a separate bowl, beat the sugar and eggs together until light and fluffy.
Add the vegetable oil, milk, and vanilla extract, and mix until well combined.
Gradually add the dry ingredients to the wet ingredients, mixing just until combined.
Fold in the chocolate chips.
Scoop the batter into a greased muffin tin, filling each cup about ¾ full.
Bake for 18-20 minutes, or until a toothpick inserted into the center comes out clean.
Allow the muffins to cool in the tin for 5 minutes before transferring to a wire rack to cool completely.
