If you're a fan of spicy food, this spicy chicken teriyaki recipe is for you. To make this dish, you will need boneless, skinless chicken thighs, soy sauce, mirin, sake, sugar, garlic, ginger, red pepper flakes, and vegetable oil. Start by marinating the chicken in a mixture of soy sauce, mirin, sake, sugar, garlic, ginger, and red pepper flakes for at least 30 minutes. Then, heat vegetable oil in a skillet over medium-high heat and cook the chicken until browned and cooked through. The addition of red pepper flakes gives this dish a nice kick of heat. Serve the spicy chicken teriyaki with steamed rice and a side of stir-fried vegetables for a satisfying and flavorful meal.