Whisk the rice vinegar, water, honey, and sea salt in a small bowl until the salt and honey are fully dissolved.
Add the shredded carrots and sliced cucumbers to the vinegar mixture and let them pickle in the refrigerator for at least 15 minutes.
Slice the pork tenderloin into thin strips to mimic the texture of pork belly and season evenly with garlic powder.
Heat the avocado oil in a large skillet over medium-high heat and sear the pork strips until they are caramelized and cooked through.
Pour the coconut aminos into the skillet and toss the pork continuously to coat each piece in a thick, savory glaze.
Steam the bao buns according to the package instructions until they are hot, soft, and pillowy.
Assemble the buns by stuffing each with the glazed pork strips, a generous portion of pickled vegetables, fresh cilantro, and a sprinkle of sesame seeds.