Preheat oven to 350 degrees F. Line a muffin tin with 12 muffin liners; set aside. In a medium bowl, combine flour, baking powder, baking soda and salt. Mix well and set aside.
In a large bowl, combine egg, sugar and butter. Mix until creamy. Add sour cream and vanilla. Now slowly add in the dry ingredients until combined. Finally, fold in chocolate chips.
Divide the batter between the muffin liners, filling them two-thirds of the way full. Bake in the preheated oven for 18-22 minutes, or until a toothpick inserted into the center comes out clean.
Notes
Consider adding extra ingredients to the batter for a boost of flavor and texture! Add dried fruit such as raisins or cranberries or chopped pecans. Be sure not to exceed a total of 1 cup of extras.
Add in a ripe mashed banana for added flavor.
Serve warm with a pat of butter for the most delicious results.