Preheat the oven to 220C, fan-forced. Line an oven tray with baking paper. Halve the zucchini lengthwise, then score the cut sides in a crisscross pattern. Quarter the pak choy lengthwise.
Step 2 — Season greens and pork
Combine 2 tsp oil and 2 tsp soy sauce in a dish or large bowl and season with pepper. Add the zucchini and pak choy and turn to coat. Put the pork and half the tonkatsu sauce in a separate large dish and turn to coat. Put the pork and zucchini, cut-side up, on the lined tray. Set the pak choy aside.
Step 3 — Bake greens and pork
Bake the zucchini and pork for 16 mins. Add the pak choy to the tray and bake for a further 5-6 mins until the pork is just cooked through and the vegetables are tender. (The pork will be cooked to blush pink, which is desired to ensure the meat is tender and juicy.) Rest the pork for 5 mins.
Step 4 — Pickle radish
Meanwhile, thinly slice the radish with a sharp knife or mandoline. Thinly slice the spring onion on an angle. Combine 2 tsp white vinegar, ½ tsp sugar and a pinch of salt in a bowl. Add the radish and spring onion and toss to coat. Refrigerate, tossing occasionally, until needed.
Step 5 — Microwave rice
Just before serving, massage the packet of rice to loosen and tear a 2cm opening for the steam to escape. Heat in the microwave for 90 secs or until heated through.
Step 6 — Slice pork and serve
Slice the pork and return to the tray. Drizzle with the remaining tonkatsu sauce, then scatter with the pickled radish mixture and a pinch of the shichimi togarashi* (the shichimi togarashi has a chilli kick; you can leave it out if you prefer). Serve the tray bake at the table with the rice.