Preheat your oven to 180°C (350°F) and line a muffin tray with paper liners.
In a large bowl, mix flour, sugar, and baking powder.
In another bowl, whisk together milk, oil (or melted butter), and egg.
Pour the wet ingredients into the dry ingredients and mix gently until combined.
Fold in the chocolate chips.
Fill the muffin cups about 3/4 full with batter.
Bake for 18–22 minutes or until a toothpick inserted comes out clean.
Let the muffins cool for a few minutes before serving.