Pat the boneless chicken thighs dry with a paper towel. In a mixing bowl, combine cornstarch, kosher salt, and freshly ground black pepper. Coat each piece of chicken evenly with the mixture.

Heat oil in a large skillet over medium-high heat for about 2-3 minutes. Once shimmering, add coated chicken thighs. Fry for 5-7 minutes on each side until golden and cooked through.

In the same skillet, reduce heat to medium and add unsalted butter, allowing it to melt. Whisk together honey, soy sauce, dark soy sauce, five-spice powder, and grated garlic until smooth.

Pour the sauce into the skillet, stirring continuously. Bring to a gentle simmer and cook for about 5 minutes until the sauce thickens.

Return the fried chicken to the skillet, ensuring they are coated in the glaze. Cook for an additional 2-3 minutes, turning occasionally.

Transfer the chicken to a serving platter. Slice into bite-size pieces and garnish with sesame seeds and chopped scallions.