In a stand mixer fitted with a paddle attachment, combine the cold water, baking soda, sea salt, mirin seasoning and soy sauce. Mix on medium speed until dissolved. Alternatively, use a large bowl and mix by hand.
To the mixing bowl, add pork mince, panko breadcrumbs, ginger, garlic cloves, spring onions, cabbage, sesame oil, Sriracha sauce and Citrus Furikake. Mix until fully combined and the mixture becomes slightly sticky and holds together.
Transfer the mixture to the fridge for 5–10 minutes to firm slightly. Meanwhile, cut each sheet of puff pastry in half lengthways to create long strips.
Divide the filling evenly and shape into logs along the centre of each pastry strip, about 4cm thick. In a small bowl, whisk together the eggs and milk, then brush along both long edges of the pastry. Fold the pastry over the filling, overlapping the edges, and press gently to seal.
Place the rolls seam-side down on a tray and refrigerate for 15 minutes to firm up as this makes portioning much easier. Preheat the oven to 190°C fan-forced.
Cut each roll into 6 equal pieces, place onto a lined baking tray, and brush with the remaining egg wash. Sprinkle with Gewürzhaus Citrus Furikake and bake for 25 minutes, or until golden and cooked through.
