In a large bowl, whisk together the flour, baking powder and soda, sugar and salt.
Add the sourdough discard, 1 1/2 cups milk, egg and oil; mix well just until combined and set aside for 5 minutes.
Spray a pancake griddle with cooking spray or grease well with butter. Heat to about 300-350 degrees; when the griddle is hot, add the remaining 1/2 cup milk to thin out the batter a bit and stir
Pour a ladleful (about 1/4 cup) pancake batter onto the hot griddle. Cook until the pancake starts bubbling on top, sprinkle on a few chocolate chips and then flip the pancake.
Cook for an additional 1-2 minutes or until the pancake is cooked through.
Serve warm with pure maple syrup or fruit preserves.