Phase 1: Preparing the Chicken and Dredge

1. Prepare the Chicken: Pat the chicken pieces thoroughly dry with paper towels. This is crucial for achieving a crispy crust, as excess moisture hinders browning and crisping. If using whole wings, separate them into flats and drumettes, discarding the tips (or save them for stock). If using thighs, cut them into roughly equal-sized pieces (about 1.5-2 inches). Season the chicken lightly with a pinch of salt and pepper if desired (optional, as the dredge and sauce are well-seasoned).
2. Mix the Dredge: In a large bowl, whisk together the all-purpose flour, potato starch (or cornstarch), baking powder, kosher salt, black pepper, garlic powder, and onion powder (if using). Ensure there are no lumps, especially from the baking powder or starch.

Phase 2: The Frying Process (Double Fry Method)

3. Set Up Your Frying Station: Pour the neutral frying oil into a large, heavy-bottomed pot (like a Dutch oven) or a deep fryer. You need enough oil for the chicken to be mostly submerged, usually about 3 inches deep. Place a wire rack over a baking sheet nearby – this is where the chicken will rest after frying. Have long tongs or a spider strainer ready.
4. Heat the Oil (First Fry): Heat the oil over medium-high heat until it reaches 300-325°F (150-160°C). Use a deep-fry thermometer or candy thermometer to monitor the temperature accurately. Maintaining the correct temperature is key. Too low, and the chicken absorbs too much oil; too high, and the outside burns before the inside cooks.
5. Dredge the Chicken: Working in batches, toss the chicken pieces in the dredge mixture, ensuring each piece is thoroughly coated. Press the coating onto the chicken firmly. Shake off any excess flour mixture. Don’t let the dredged chicken sit for too long before frying, as the coating can become gummy.
6. First Fry: Carefully lower the dredged chicken pieces into the hot oil, one by one. Do not overcrowd the pot! Fry in batches (typically 5-7 pieces at a time, depending on pot size) to maintain the oil temperature. Fry for about 10-12 minutes for wings/smaller thigh pieces, turning occasionally, until the chicken is cooked through and the crust is set and lightly golden (it won’t be deeply brown yet). The internal temperature should reach 165°F (74°C).
7. Rest the Chicken: Using tongs or a spider strainer, remove the chicken from the oil, letting excess oil drip off. Place the chicken pieces in a single layer on the prepared wire rack. Let the chicken rest for at least 10-15 minutes. Allow the oil temperature to return to 300-325°F between batches. Repeat steps 5-7 until all chicken is cooked through its first fry.

Phase 3: Making the Sauce

8. Combine Sauce Ingredients: While the chicken is resting after the first fry (or while frying the last batches), prepare the sauce. In a medium saucepan, combine the rice syrup (or corn syrup/substitute), gochujang, soy sauce, water, rice vinegar, gochugaru, minced garlic, and grated ginger.
9. Simmer the Sauce: Place the saucepan over medium heat. Bring the mixture to a gentle simmer, stirring constantly to prevent scorching, especially around the edges. Let it simmer for 3-5 minutes, stirring occasionally, until the sauce slightly thickens and the flavors meld. The garlic should become fragrant, and the sauce should be glossy.
10. Finish the Sauce: Remove the saucepan from the heat and stir in the toasted sesame oil. Set aside. The sauce will thicken slightly more as it cools.

Phase 4: The Second Fry and Coating

11. Heat the Oil (Second Fry): Increase the heat under the frying pot and bring the oil temperature up to 350-375°F (175-190°C). Again, monitor carefully with a thermometer.
12. Second Fry: Working in batches again (don’t overcrowd!), carefully return the rested chicken pieces to the hotter oil. Fry for another 2-4 minutes, turning occasionally, until the crust is deeply golden brown, blistered, and exceptionally crispy. Keep a close eye on it, as it can brown quickly at this higher temperature.
13. Drain Again: Remove the double-fried chicken from the oil, letting excess oil drip back into the pot. Return the chicken to the wire rack briefly. Allow the oil temperature to recover between batches. Repeat until all chicken is double-fried.

Phase 5: Sauce and Serve

14. Coat the Chicken: Once all the chicken is double-fried and still hot, transfer it to a large mixing bowl. Pour the prepared Yangnyeom sauce over the hot chicken. Using tongs or spatulas, gently toss the chicken until every piece is evenly coated with the glossy sauce. Do this step just before serving to maintain maximum crispiness.
15. Garnish and Serve: Immediately transfer the sauced chicken to a serving platter. Sprinkle generously with toasted sesame seeds and sliced scallions. Serve hot and enjoy the incredible crunch!