For Pickled Carrots and Daikon: Place carrots, daikon and salt in a colander over the sink and mix together. Allow to sit for 1 hour, tossing together every 15 minutes to remove the natural water from the vegetables. Thoroughly rinse and place into a mixing bowl. Add red onion.
Place sugar, vinegar and water in a small pot and bring to a simmer until sugar dissolves. Allow to cool for 10 minutes.
Pour sugar mixture over veggies and place in the refrigerator for an hour.
For Pork Belly 1st cooking process: First rinse and dry the pork belly. Heat a dutch oven over high heat with a bit of oil in it. Give the pork belly a good sear on each side, at least 15 minute Remove from pot. Heat a bit more oil and then add shallot, ginger and garlic saute until brown. Carefully pour in cooking wine and soy sauce scraping up the bits on the bottom of pan. Add the pork belly back into pot, dump in the Chinese braising spice mix, cover with the water and set it on low and braise for 2-3 hours, checking after 1-2 hours to test how tender the pork is. The longer you cook the more tender it will be. Ideally, you want it to be fork tender, about 2 1/2 hours. Remove from pot and let rest, tented with foil. Slice about 1/2-inch thick pieces.
2nd Cooking process: Place basting glaze into a mixing bowl and whisk together. Add pork belly and toss together until well coated.
Place 2 tablespoons oil into a grill pan and heat over medium-high heat. Sear the pork belly on each side for about 3-4 minutes. Glazing often. Remove from heat and set aside.
To assemble: Open steamed bun and spread a bit of the mayo on the bottom. Place a couple pieces of pork belly into each bun and top with cucumber slices followed by a small amount of the pickled veggies.
CHINESE BRAISING SPICE MIX:
2 tablespoons of sugar.
4 whole star anise.
1 cinnamon stick.
1 tsp whole clove.
1 tsp whole peppercorns.
2 whole red chillies (optional, I like it a little spicy).