To make the Pancakes: Combine the sourdough starter, flours and milk in a bowl; set aside for 30 minutes.
Add oil, baking soda, salt and egg replacer and stir until well combined. Fold in the corn and scallions.
Heat a griddle or a pan over medium heat. Lightly grease the pan, then scoop a ladleful of batter onto the pan. Cook until the surface bubbles and edges are slightly dry, flip and cook on the other side until bottom is golden brown.
Repeat with the remaining batter.
For the Salad: Combine all the ingredients and set aside for at least 10 minutes for the flavors to mingle.
To Serve: Scoop 1tbsp of the salad and 1tsp sour cream (if using) onto each warm pancake. Serve hot or at room temperature.