In a large bowl, whisk together the sourdough, oil, eggs, milk, vanilla and sugar. Mix well.
Add the flour, salt, baking soda and baking powder. Whisk together gently just until combined.
Use a spatula to fold in the mini chocolate chips.
Place paper liners in two muffin pans (a total of 24 muffins).
Scoop the batter evenly into each paper liner, filling the muffin cups about 3/4 full.
Bake at 400º Fahrenheit for 5 minutes, then without opening the oven, reduce the temperature to 325º and bake for an additional 10-12 minutes, or until the muffins test done.
Store in an airtight container at room temperature.
The calories shown are based on the recipe making 24 muffins, with 1 serving being 1 muffin. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information.**