Bourbon Sauce - In a medium bowl, whisk together chicken stock, bourbon whiskey, soy sauce, maple syrup, tomato paste, apple cider vinegar, black pepper, and chili flakes. Set aside.
Make the Slurry - In a small bowl, whisk together cornstarch and water. Set aside.
Cook the Chicken - Set a wok or large nonstick frying pan over medium-high heat. Once hot, add vegetable oil and sesame oil. Add the chicken and spread it into one layer. Allow it to cook for 2 minutes without moving. Stir-fry until no longer pink, about 1 minute.
Cook the Aromatics - Add the garlic and ginger, and stir-fry for 30 seconds.
Cook the Sauce - Add in bourbon sauce mixture. Simmer for 2 to 3 minutes, occasionally stirring to help some of the alcohol evaporate and for the sauce to reduce.
Thicken the Sauce - Stir the bowl of cornstarch slurry, then add it to the pan. Stir until the sauce thickens, 60 to 90 seconds.
To Serve - Garnish with sesame seeds and green onions.
Make it Gluten-Free: Use coconut aminos or gluten-free tamari instead of soy sauce.
Make it Grain-Free: Use 3 tablespoons of arrowroot powder instead of cornstarch. Mix with ⅓ cup of water.
Storing: Cool completely and store in an airtight container for up to 3 days.
Reheating: Warm over medium-low heat on the stovetop. Alternatively, cover and cook on the high setting in the microwave until hot, about 30-second increments.