Mom's BBQ Chicken (Umma's Dak Gogi)

Ingredients

• 1 1/4 cup soy sauce
• 1/2 cup packed dark brown sugar
• 6 scallions, thinly sliced on an angle
• 3 tablespoons rice vinegar
• 3 tablespoons maple syrup
• 2 tablespoons gochujang (korean chile paste)
• 2 tablespoons toasted sesame oil
• 2 tablespoons grated peeled fresh ginger
• 2 tablespoons roasted sesame seeds
• 6 cloves garlic, grated or minced
• pinch of kosher salt or sea salt
• freshly ground black pepper
• 8 boneless skinless chicken thighs
• vegetable oil, for grilling
• doenjang mayonnaise (see below), for serving
• 1/2 cup mayonnaise, preferably kewpie or a korean brand
• 1 tablespoon doenjang (korean soybean paste)