Preheat your oven to 190°C (170°C fan) and line a large baking tray with baking parchment. The paper should be large enough that you can fold it up around the meatloaf later for easy lifting.

Sweat the onion and garlic: Heat a drizzle of oil in a large frying pan over a medium heat. Add the diced onion and cook for 4-5 minutes until it turns translucent and smells sweet — you'll notice the sharp raw onion aroma soften into something mellow. Add the minced garlic and cook for 30 seconds until fragrant, then set aside to cool slightly.

Mix the meatloaf base: In a large mixing bowl, combine the minced beef, cooled onions and garlic, rolled oats, eggs, milk, tomato purée, Worcestershire sauce, dried thyme, salt, and pepper. Use your hands to mix everything together — you're looking for a uniform colour and texture, with no streaks of egg or patches of dry oats. The mixture should feel moist but hold together when pressed.

Shape the loaf: Tip the mixture onto the lined baking tray and shape it into a rounded loaf about 20cm long and 8cm tall. Don't pack it too tightly, or the meatloaf will become dense. You want it to feel firm but slightly springy when you press it.

Prepare the glaze: In a small bowl, whisk together the soft light brown sugar, tomato ketchup, and apple cider vinegar until the sugar has mostly dissolved. You'll have a thick, sticky, glossy sauce that smells tangy and sweet.

Apply the first glaze layer: Spoon about half the glaze over the shaped meatloaf and spread it evenly with the back of the spoon. Use a pastry brush if you have one — it helps you get an even coat without disturbing the loaf.

Bake the meatloaf: Place the tray in the preheated oven and bake for 30 minutes. After 30 minutes, remove the tray and spoon the remaining glaze over the top. Return to the oven for another 15-20 minutes. You'll know it's done when the internal temperature reaches 71°C, the glaze is bubbling and darkened to a deep mahogany colour, and the edges of the meatloaf are slightly caramelised.

Rest before slicing: Remove the meatloaf from the oven and let it rest on the tray for 10 minutes. This is crucial — the internal juices need time to redistribute. During this time, the loaf firms up slightly, and you'll see the glaze set into a sticky, glossy coating. Slice with a sharp knife and watch the steam rise.