In a mixing bowl, whisk together soy sauce, honey or brown sugar, and toasted sesame oil.

Bring a large pot of water to a boil and add the sweet potato glass noodles. Cook until tender and chewy, then drain and rinse under cold water.

In a skillet, heat cooking oil and pour in beaten eggs, swirling to create an even layer. Cook until set and slice into strips.

Add oil if necessary and sear thinly sliced beef or pork in the skillet for about 3-4 minutes, seasoning with salt and pepper.

Sauté onions in the skillet for 2-3 minutes, add carrot and mushrooms, then add spinach and cook until wilted.

Return cooked noodles to the skillet with sautéed vegetables. Pour the prepared sauce over and add the meat and egg strips. Toss gently.

Transfer the Japchae to a serving platter and garnish with toasted sesame seeds.