In a small bowl, combine mustard powder and hot water, and mix well.

Place the mustard mixture bowl over a pot of hot water to let it steam and activate its spiciness.

In a food processor, combine garlic cloves, white vinegar, and salt.

Peel, core, and roughly chop a small apple, then add it to the food processor.

Blend the apple mixture in the food processor for about one minute until it becomes a smooth puree.

Add the apple puree to the bowl with the mustard mixture.

Stir in honey and sesame oil until well combined.

Transfer the sauce to an airtight container and refrigerate until ready to serve.

Remove the tips from the pine nuts using your fingernails.

Place the pine nuts on parchment paper and crush them coarsely with a rolling pin.

Prepare about 7 ginkgo nuts for garnish.

Pat the beef steak dry with a paper towel to remove excess moisture.

Slice the beef very thinly, about 1/8-inch thick.

Lay the beef slices flat and season with salt and ground black pepper.

Drizzle sesame oil over the beef and gently massage it in.

Generously coat both sides of the beef slices with glutinous rice flour.

Heat a non-stick pan over medium-high heat and add a drizzle of cooking oil.

Pan-fry the coated beef slices in batches until they are cooked through and slightly browned.

Transfer the cooked beef to a plate lined with parchment paper to drain any excess oil.

In the same pan, briefly cook the ginkgo nuts.

Peel the Korean pear and julienne it into thin matchsticks.

Arrange the cooked beef on a large serving platter.

Garnish with a pile of julienned pear, the cooked ginkgo nuts, and fresh perilla leaves.

Sprinkle the crushed pine nuts generously over the cooked beef.

Serve the beef salad with the chilled mustard-garlic sauce on the side.