In a small bowl, whisk together soy sauce, pineapple juice, brown sugar, rice wine, rice vinegar, minced garlic, ginger paste, sesame oil, and black pepper until the sugar is fully dissolved. This combines all your flavor components upfront, ensuring they meld together as the chicken cooks rather than layering unevenly. Set the sauce aside until ready to use.

Heat a large skillet or braising pan over medium-high heat until it's hot. Add the chicken drumsticks and let them cook undisturbed for 2-3 minutes per side until they develop a light golden crust—this browning adds depth to the final flavor. You're not cooking them through at this stage, just building color and developing the Maillard reaction.

Pour the teriyaki sauce from Step 1 over the seared drumsticks, ensuring they're mostly submerged. Bring the liquid to a gentle boil over medium-high heat, then immediately reduce to medium, cover the pan, and cook for 10-12 minutes total, turning the chicken halfway through (about 5-6 minutes per side). I like to keep the heat at medium rather than medium-high during this phase because it allows the chicken to cook through gently while the sauce infuses evenly without scorching.

Remove the lid and increase the heat to medium-high. Whisk cornstarch with 1 tablespoon of water to create a slurry, then stir it into the simmering sauce. Continue cooking uncovered for 3-5 minutes, stirring occasionally, until the sauce reduces by about half and becomes glossy and thick enough to coat the back of a spoon. The chicken is already cooked through at this point—you're concentrating the flavors and thickening the glaze to coat the drumsticks beautifully.

Remove from heat and toss the drumsticks gently in the glaze to coat them evenly on all sides. Transfer to a serving plate and sprinkle with toasted sesame seeds for garnish and a nutty finish. Serve immediately over steamed rice to catch all the delicious sauce.