Sift sugar, flour, cocoa powder, baking powder, baking soda, and salt into a large bowl.
Add the egg, oil, sour cream, and vanilla to a separate bowl and whisk together.
Pour the wet mixture into the dry with half of the chocolate chips, and use a spatula or wooden spoon to mix until combined. Do not over mix.
Add the remaining chocolate chipes and lightly mix.
Scoop into prepared muffin tin.
Bake for 14-17 minutes or until a toothpick comes out clean.
Allow the muffins to cool in the pan for about 5-10 minutes after removing them from the oven.
Use a butter knife or offset spatula to gently loosen the edges of each muffin from the pan.
Carefully transfer the muffins from the pan to a wire cooling rack.
Serve and enjoy!
Notes
Use a cookie scoop to measure out the same amount of batter for each muffin. This ensures that all the muffins bake evenly and have a uniform size...plus it helps prevent spills and keeps the muffin batter from dripping and sticking to the pan.
Use full fat ingredients for the best flavor and texture.
Allow the muffins to cool in the pan for about 5-10 minutes after removing them from the oven. This helps them set and prevents them from falling apart when transferring.
Use a butter knife or offset spatula to gently loosen the edges of each muffin from the pan. This will make it easier to remove them without sticking.