In a small bowl whisk together the mayonnaise, chili paste, sesame oil, rice wine vinegar, and soy sauce. Set aside while you prepare the crabs.
Heat at least 4 inches of oil in a large heavy saucepan or Dutch oven or a deep-fryer to 350 degrees F.
Combine the flour and half of the Essence in a shallow bowl. Stir to blend well. In another shallow bowl whisk the eggs and milk together with the remaining Essence. Place the panko in a third shallow bowl.
Dredge each crab first in the flour, shaking to remove any excess, then in the egg wash, and finally in the panko. Set aside on a plate while you prepare the remaining crabs.
When the oil has reached the desired temperature, fry the crabs, 1 at a time, until golden brown and crispy on both sides, 3 to 4 minutes per side. Transfer to paper towels to drain while you fry the remaining crabs.
Drizzle about 2 tablespoons of the Spicy Mayonnaise around the perimeter of each of 4 dinner plates and top each plate with a crab. Garnish with the scallions and a little extra Essence around the edge of the plate. Serve immediately.