Take the beef shank chunks out of the freezer, and once the surface has thawed, place them in a pan and sear the surface, flipping several times.

Beef Shank Boiled Pork Slices (Suyuk)
A dish featuring beef shank boiled until tender and chewy, served with a sweet and sour chive salad dressing.
What You'll Need
Instructions
Stand the beef shank chunks on their sides to sear them as well.
Place the seared beef shank into a slow cooker.
Add 1/2 onion, 20 whole peppercorns, and 20 garlic cloves to the slow cooker.
Set the slow cooker to high and set the timer for 4 hours if available.
⏱️ 240m 0sAfter 4 hours on high, remove the thoroughly boiled beef shank from the slow cooker and let it cool slightly.
Once the beef shank has cooled sufficiently, place it on a cutting board and slice it as thinly as possible.
Mix 3 tbsp soy sauce, 2 tbsp vinegar, 2 tbsp water, and 1 tbsp red chili powder to create the soy-vinegar dressing.
Prepare the chive salad by pouring the soy-vinegar dressing over the chives cut into appropriate lengths and thinly sliced onions.
Serve by arranging the thinly sliced beef shank nicely on top of the chives and onions drizzled with the soy-vinegar dressing.