Preheat your oven to 375°F (190°C), line a muffin tin with paper liners, or lightly grease the muffin pan.
Whisk together the flour, cocoa powder, baking powder, baking soda, and salt in a large bowl.
Add the eggs, sugar, melted butter, milk, and vanilla extract one by one to another bowl. Gently mix until well combined.
Add the dry ingredients into the bowl of wet ingredients, little by little. Gently fold the wet and dry ingredients together using a wooden spoon or spatula. Mix until just combined; do not overmix.
Toss the chocolate chips with a small amount of flour. This helps prevent them from sinking to the bottom during baking. Gently fold half the coated chocolate chips into the muffin batter.
Using a spoon or scoop, evenly distribute the batter into the muffin cups, filling each about ⅔ to ¾ full. This allows room for the muffins to rise. Top the batter with the remaining chocolate chips.
Place the muffin pan in the preheated oven and bake for approximately 18-20 minutes, or until a toothpick inserted into the center of a muffin comes out with a few moist crumbs. Avoid over-baking, as it can result in dry muffins.
Once baked, remove the muffins from the oven and allow them to cool in the muffin pan for a few minutes. Then, transfer them to a wire rack to cool completely.
Delicious Double Chocolate Chip Muffins are ready to be served!