Candy the Walnuts: In a small saucepan, combine the sugar and water. Bring to a boil over medium heat, stirring until the sugar is dissolved. Add the walnuts and cook for 2-3 minutes until the walnuts are caramelized and coated with the syrup.
Dry the Walnuts: Using a slotted spoon, remove the walnuts and spread them out on a piece of parchment paper or a baking sheet to dry and harden.
Prepare the Shrimp
Season the Shrimp: In a medium bowl, season the peeled and deveined shrimp with salt and black pepper.
Coat the Shrimp: In a separate bowl, whisk the egg whites until frothy. Dip each shrimp into the egg whites, then coat them in cornstarch, shaking off any excess.
Fry the Shrimp: Heat about 1 inch of vegetable oil in a large skillet or wok over medium-high heat. Fry the coated shrimp in batches for 2-3 minutes on each side, or until golden brown and crispy. Remove the shrimp from the oil and drain on a paper towel-lined plate.
Prepare the Honey Sauce
Make the Sauce: In a small bowl, whisk together the mayonnaise, honey, sweetened condensed milk, and lemon juice until smooth.
Coat the Shrimp: In a large mixing bowl, toss the fried shrimp with the honey sauce until evenly coated.
Assemble and Serve
Add the Walnuts: Add the candied walnuts to the shrimp and gently toss to combine.
Serve: Transfer the honey walnut shrimp to a serving platter and garnish with additional walnuts if desired. Serve immediately.