Preheat oven to 400 degrees F. Lightly spray 48 miniature muffin cups.
Mix flour, white sugar, brown sugar, baking powder, and salt together in a bowl.
Lightly beat egg in a separate bowl; stir in milk, vegetable oil, and vanilla extract. Mix liquid mixture into flour mixture until incorporated. Fold in chocolate chips. Fill muffin cups 3/4 full with batter.
Bake in the preheated oven until a toothpick inserted in a muffin comes out clean, 10 to 11 minutes. Cool for 1 minute before transferring muffins to a wire rack.