Make pickle by combining red cabbage, apple cider vinegar, boiling water, sugar, and coriander seeds. Pour over red cabbage and allow to sit for at least 3 hours.
Freeze pork mince for 1 to 2 hours so it's semi-frozen.
Mix mince with lemongrass, shallot, garlic, soy sauce, fish sauce, oyster sauce, hoisin, salt, honey, panko breadcrumbs, baking powder, and black pepper using a food processor for about 10 minutes until texture is sticky. Alternatively, use hands to vigorously mix in one direction for about 5 minutes.
Using clingfilm, roll the mixture into a log shape. Place onto puff pastry, fold over to cover, and cut off any excess.
Cut into sausage rolls. If pastry feels soft, freeze for 15-20 minutes to firm up.
Eggwash and sprinkle with sesame seeds.
Bake at 180°C fan for 25 to 30 minutes.