Heat the extra-virgin olive oil, 3 turns of the pan, in a deep skillet over medium heat. Add shallots to hot oil and saute them for 2 minutes. Add vinegar and soy and whisk into duck sauce. Reduce heat to low. Add hot sauce to dressing and pile in half the spinach. Turn spinach carefully with tongs. When it wilts down, 2 minutes, add the remaining greens and wilt. Season the warm salad with salt and pepper to your taste. Serve the spinach with toasted sesame seeds sprinkled over top.