Step 1

Preheat oven to 350 degrees. Line a muffin tin with paper liners or spray with non-stick spray.

Step 2

Add the butter, brown sugar, and sugar to a mixing bowl and beat on medium speed until light and fluffy.

Step 3

Beat in the eggs until well incorporated.

Step 4

Stir in the sour cream, buttermilk, and vanilla until combined.

Step 5

Add the flour, baking soda, baking powder, and salt to the bowl and stir by hand until the flour has just disappeared into the batter. Do not overmix or your muffins will be tough.

Step 6

Gently fold the chocolate chips into the batter with a rubber spatula.

Step 7

Fill the muffin tins 2/3 full.

Step 8

Bake for 12-14 minutes or until the tops spring back when lightly pressed.

Step 9

Cool for 10 minutes in the muffin tin before removing to the counter to cool completely.