Making marinade & marinating chicken: Mix gochujang, soy sauce, rice vinegar, sesame oil, garlic, and ginger. Add the chicken thighs and ensure they are completely covered with the marinade. Let them marinate for at least 1 hour (even better: overnight).
Preparing sesame sauce: Mix tahini, soy sauce, rice vinegar, sesame oil, lime juice, and zest. Gradually add water until you have a creamy sauce. Stir in the nigella seeds or black sesame and set aside.
Making coleslaw: Finely chop the white and red cabbage. Grate the apple and carrot. Mix with mustard, Greek yogurt, apple cider vinegar, walnut oil, and finely chopped chives to create a fresh salad.
Cooking chicken: Heat a small amount of sesame oil in a pan. Cook the chicken on both sides until nicely colored and cooked through. Remove from the pan and slice.
Preparing quinoa-cauliflower rice: Wash the quinoa and cook in plenty of water according to the package instructions. Skim off any foam if necessary. Add the cauliflower in the last minute, drain, and keep warm.
Avocado & mango: Slice the avocados and dice the mango.
Plating: Lightly grease a bowl with sesame oil. Spoon the warm quinoa-cauliflower rice into it, press down, and invert onto a plate to create a nice round base. Arrange the coleslaw, sliced chicken, avocado, mango, and some watercress around it. Serve the sesame sauce on the side.