In a bowl mix together the flour, baking powder, salt, and garlic powder. Stir in water a little at a time until a thick pancake like batter forms.
Stir in the bean, corn, red onion, and cilantro.
Heat the oil in a large frying pan over medium heat. Once hot, using about a tablespoon sized portion, drop the batter into the pan, space each portion apart so they are not touching. Cook until golden brown and crisp, then flip over and do the same to the other side.
When both sides are nicely browned, remove them to a paper towel to drain any excess oil. Season with salt and serve.
In a bowl whisk together the mayo and chipotle. Use your preferred amount of chipotle to taste. Season with salt to taste.
Serve the cakes with sauce.