Spicy Chicken Bulgogi

Name: Spicy Chicken Bulgogi
Cuisine: Asian, Korean
Ingredients: 2 pounds boneless chicken thigh (You can use chicken breast if you want); 2 to 3 tablespoons gochugaru (고추가루), Korean red chili pepper flakes; 1 tablespoon sugar (or light brown sugar) (or your favorite sugar substitute); 3 tablespoons soy sauce; 2 tablespoons rice wine or mirin (white wine is good too); 2 tablespoons gochujang (고추장), Korean red chili pepper paste; 2 tablespoons maesil chung, 매실청 (or 2 to 3 tablespoons pineapple juice or grated apple); 1 tablespoon sesame oil; 1/4 medium onion, grated (about 1/4 cup); 2 tablespoons minced garlic; 2 teaspoons grated ginger; 1/2 teaspoon salt; pepper to taste; 2 tablespoons chopped scallions; 1 teaspoon sesame seeds