Step 1

Mix the chicken chunks with the milk in a large bowl. Cover and refrigerate for at least for 30 minutes.

Step 2

Combine soy sauce, black pepper, garlic, ginger, and rice syrup in a small bowl. Mix well with a wooden spoon.

Step 3

Drain the chicken in a colander and squeeze out excess milk with your hands. Put the chicken back to the bowl and pat dry with paper towel to remove excess moisture. Add the seasoning sauce to the chicken in the bowl. Mix well with the wooden spoon or by hand.

Step 4

Prepare a cast-iron skillet or grill pan over medium-high heat. Drizzle the vegetable oil all over the grill. Put the chicken on the grill pan, spreading it out so it cooks in an even layer. Reduce the heat to medium and cover. Cook for 5 to 6 minutes. Open and turn the chicken over. Increase the heat to medium high, and scrape the marinade in the bowl onto the chicken, flipping the meat from time to time and moving it around so that it doesn't burn or overcook. Using tongs, rub the butter all over chicken, turn over and cook or another minute. To check to see if the chicken is fully cooked, insert a skewer; if the juice runs clear, it's fully cooked. If it's a little pinkish it needs to be cooked longer.

Step 5

Transfer to a plate and sprinkle with the chopped green onion. Serve with rice, kimchi, and a few more side dishes.