Salt zucchini and prepare flax egg if needed.
Squeeze zucchini in a clean tea towel, removing liquid, until it appears dry and reduces in volume (1 cup will become about ¾ cup).
Mix corn, zucchini, cilantro, egg/flax and oil in a medium bowl.
In a small bowl, combine remaining dry ingredients.
Stir flour mixture into corn mixture. Batter will be thick and a bit crumbly but should stay together when cooked. If needed, add more flour or oil.
Heat 1-2 Tbsp oil of choice in skillet over medium heat (cast iron recommended).
Once hot, add ¼ cup batter, flattening into a ½ inch thick circle.
Cook fritters 2-3 minutes per side, until nicely browned, moderating heat as needed.
Cook in batches, adding more oil if necessary.