In a large bowl, combine sesame oil, garlic paste, and grated ginger. Microwave until fragrant, 40 to 60 seconds.
Whisk in ¼ cup water, sugar, gochujang, and soy sauce until smooth. Set aside.
Heat vegetable oil in a Dutch oven over medium-high to 350°F.
In another bowl, whisk flour, cornstarch, and remaining 1½ cups water until smooth.
Set a wire rack inside a rimmed baking sheet.
Add half the wings to the batter and coat. Let excess drip off and add to hot oil.
Fry until light golden and beginning to crisp, about 7 minutes. Transfer to rack.
Return oil to 350°F and repeat with remaining wings. Let second batch rest 5 minutes.
Increase oil to 375°F. Fry all wings together until deep golden and crispy, about 7 minutes.
Transfer to rack and let rest 2 minutes.
Toss wings in the sauce. Return to rack for 2 more minutes before serving.