In a large mixing bowl, combine the ground beef or pork, napa cabbage, green onions, grated carrot, minced garlic, soy sauce, sesame oil, and ground black pepper.

Use your hands to mix the filling until well combined.

Take a mandu wrapper and place a teaspoon of filling in the center.

Moisten the edges of the wrapper with water, fold it over the filling, and press firmly to seal.

Once all your mandu are assembled, you can choose to steam, boil, or pan-fry them.

If steaming, place them in a steamer basket lined with parchment paper and steam for about 10 minutes.

For frying, heat oil in a pan and cook until golden brown on both sides, about 3-4 minutes each.

Transfer the cooked mandu to a plate and serve with soy sauce or your favorite dipping sauce.

If you have any leftovers, let them cool completely before storing.