Squeeze moisture from tofu using cheesecloth and transfer to a large bowl.

Boil cabbage in salted water until limp, then drain, rinse, chop finely, and squeeze out moisture using cheesecloth. Add to the bowl with tofu.

Boil bean sprouts in salted water until soft, then drain, rinse, chop finely, and squeeze out moisture using cheesecloth. Add to the bowl with tofu and cabbage.

Add kimchi, ground beef, eggs, sesame oil, pepper, and remaining salt to the bowl. Mix until thoroughly combined.

Place 1/2 tablespoon of mixture in the center of a dumpling wrapper. Moisten edges with egg white, fold over to make a semicircle, and press down to seal.

Warm 2 tablespoons of cooking oil in a skillet over medium-high heat. Add 10-12 dumplings and cook until browned, 2-3 minutes per side.

Lower heat to medium, add 1/4 cup water, cover, and steam for 4-5 minutes, until plump and lightly browned.

Repeat the process until all dumplings are cooked.

Stir together rice vinegar and soy sauce in a small bowl for dipping sauce.

Serve the dumplings hot with the dipping sauce.