Preheat the oven to 220C, fan-forced. Line an oven tray with baking paper. Peel the sweet potatoes and cut into 2cm chunks. Trim the beans. Finely chop the white part of the spring onion, then thinly slice the green part on an angle. Crush or finely chop 2 garlic cloves.
Step 2 — Make meatloaf
Put the beef mince, breadcrumbs, white part of the spring onion, garlic, 1 egg and 2 tsp soy sauce in a large bowl and season with salt and pepper. Using damp hands, combine well, then shape into an oval loaf (see Make it yours).
Step 3 — Roast meatloaf
Put the meatloaf on the lined tray and brush with 2 tsp vegetable oil. Roast for 20 mins, then brush with half the tonkatsu sauce and roast for a further 10 mins or until cooked through.
Step 4 — Make mash
While the meatloaf is roasting, put the sweet potato in a medium saucepan of cold salted water and bring to the boil. Reduce the heat to medium and cook for 10 mins or until tender. Drain, then return to the pan and mash until smooth. Add 20g butter, season with salt and pepper and stir to combine.
Step 5 — Cook beans and serve up
Meanwhile, bring a small saucepan of water to the boil. Add the beans and cook for 2-3 mins until tender. Drain. Slice the meatloaf. Divide the meatloaf, beans and sweet potato mash among plates. Drizzle with the remaining tonkatsu sauce, scatter over the remaining spring onion and enjoy!
Step 6 — Make it yours
If you prefer, make individual meatloaves by dividing the mince mixture into 2 equal portions before shaping into logs. Reduce the roasting time by 5 mins.