Make the marinade: In a mixing bowl, add 4 tbsp soy sauce, 2 tbsp mirin, 2 tbsp sugar, grated Fuji Apple, minced garlic, 1 tsp gochujang, 1 tbsp sesame oil and a pinch of sesame seeds and black pepper. Mix it all up and set it aside.
Thinly slice beef into strips (skip this step if using pre-sliced store bought meat). Add one by one into the mixing bowl with the marinade along with the sliced onions and chopped scallions. Toss together and mix well. Cover with plastic wrap and refrigerate for at least 1 hour (See notes).
In a large nonstick pan, stir-fry the marinated meat/veggies on medium-high heat until meats are fully cooked (3-5 minutes).
Meanwhile, cook 8 oz gnocchi in salted boiling water until fully cooked or until they float to the surface (3-5 min). Use a slotted spoon or strainer to scoop up gnocchi and add into the pan with the bulgogi. Add some pasta water and give it a nice toss to coat the gnocchi with the sauce. Then remove from heat.
Plate it up, garnish and enjoy! Yummmy!