Preheat your oven to 400°F. Slice the sweet potato into 1/2-inch rounds, season with sea salt and black pepper, and roast on a parchment-lined tray for 20-22 minutes until tender.
While potatoes roast, place the chicken breast in a small saucepan and cover with water. Bring to a very gentle simmer and cook for 12-15 minutes until the internal temperature reaches 165°F.
In a small mixing bowl, whisk together the tahini, miso paste, rice vinegar, toasted sesame oil, grated fresh ginger, and minced garlic until the dressing is silky and emulsified.
Place the shredded green and purple cabbage into a large bowl and toss thoroughly with the miso-tahini dressing until every ribbon is coated.
Remove the chicken from the water, let it rest for 3 minutes, then slice into thin strips.
Plate the dressed cabbage salad, top with the sliced poached chicken, and serve the roasted sweet potato rounds on the side.
Garnish the entire dish with sesame seeds for a final touch of texture.