Combine shrimp ingredients, except green onions, in a bowl. Store in the fridge until needed.
Combine the first 6 ingredients for the pancakes in a medium bowl. Beat the egg in a second bowl; mix in the milk, then add the corn. Add this mixture to the dry mixture and mix until just combined. Place the oil in a non-stick griddle or frying pan set to, or over, medium to medium-high heat. Pour on 2" round portions of the batter. Flip corn cakes once they begin to slightly bubble on top. Cook for 1 to 2 minutes on the other side. Arrange the corn cakes on a serving platter. Top each pancake with an equal amount of the shrimp, garnish with sliced green onion, and serve.
Note: The kernels cut off one cooked and cooled, large fresh cob of corn, should yield the 3/4 cup required for this recipe. If you use frozen corn, thaw and pat the kernels dry before using.