Preheat your oven to 350°F (175°C) and line a muffin tin with paper liners.
In a mixing bowl, combine flour, cocoa powder, sugar, baking powder, baking soda, and salt.
In another bowl, whisk together the oil, eggs, vanilla extract, and milk.
Pour the wet ingredients into the dry ingredients and stir until just combined.
Fold in the chocolate chips until evenly distributed.
Divide the batter evenly among the muffin cups, filling each about 2/3 full.
Bake in the preheated oven for 18-20 minutes or until a toothpick comes out clean.
Allow muffins to cool in the pan for 5 minutes before transferring to a wire rack.
Enjoy warm or at room temperature!
Store any leftovers in an airtight container.