Preheat oven to 350°F (180°C).
Prepare a 9x5-inch loaf pan.
In a bowl, whisk together sugar and softened butter (5-6 minutes) until smooth and paste-like.
Add eggs, sour cream, milk, and vanilla extract. Mix well (batter will curdle, which is normal).
In a separate bowl, combine flour, baking powder, and salt.
Add dry ingredients to wet batter and mix until just combined.
Fold in chocolate chips.
Pour batter into prepared loaf pan.
Top with additional chocolate chips.
Bake for 1 hour or until golden brown and toothpick comes out mostly clean.
Let cake cool in pan for 10 minutes before transferring to wire rack.
