Pre-heat the oven to 425°F
Using cooking spray coat the muffin pan. Make sure that the whole top of the muffin pan is covered, not just the part that the batter goes into.
Place paper muffin/cupcake liners into the muffin pan.
Combine dry ingredients (flour, baking powder, baking soda, salt, sugar) in a medium bowl using a whisk so that everything is well combined. Stir in 1 ¾ cups of the chocolate chips.
In a separate bowl combine all the wet ingredients (melted butter, eggs, milk, vanilla), making sure the eggs are well incorporated.
Pour the wet ingredients into the dry and stir until *just* combined.IMPORTANT: Avoid over mixing! If you stir too much, the muffins will become too dense, not rise and become more like a puck. The muffins should be fluffy and moist, so all you need to do is combine the ingredients until *just* combined. Once the dry ingredients dissolve into the wet, you're done mixing! Scoop out the batter evenly into each section of the muffin pan. Try to fill the muffin tins as close to the top as possible in order to help those delicious muffin top dome rise.
Sprinkle the tops of the batter with the remaining chocolate chips and the coarse decorative sugar.
Bake in the oven for 7 minutes at 425°F (middle rack) then reduce the heat to 375°F and bake for 15-20 min. (The muffins stay in the oven when you lower the temperature)
Once the muffins are finished baking cool in the muffin pan for 5-10 minutes.
Transfer muffins to a cooling rack. They're great served warm with a little butter.
