Preheat your oven to 200°C (400°F) fan-assisted. While it heats, place a large rimmed baking sheet in the oven to warm up — this helps the vegetables start sizzling the moment they hit the tray. (You’ll hear a gentle hiss when they land.)

Prepare the vegetables: In a large mixing bowl, toss the potato halves, onion wedges, pepper strips, and courgette pieces with the olive oil, balsamic vinegar, minced garlic, dried thyme, smoked paprika, salt, and black pepper. Use your hands to massage the seasoning into every piece — the oil should coat them evenly, making them glisten. (The smell of garlic and paprika at this stage is already promising.)

Arrange on the tray: Carefully remove the hot baking sheet from the oven. Spread the seasoned vegetables in a single layer, leaving small gaps between pieces so they roast rather than steam. Nestle the sausages among the vegetables, ensuring each sausage touches the tray directly for good browning. (You’ll hear a satisfying sizzle as they make contact.)

Roast for 20 minutes: Place the tray in the oven and roast undisturbed. After 20 minutes, the potatoes should be starting to soften at the edges, and the sausages will have begun to colour. (A rich, savoury aroma will start filling your kitchen.)

Flip and finish: Remove the tray from the oven. Use tongs to turn each sausage and give the vegetables a gentle stir, bringing any pale sides to the top. Return to the oven for another 15–20 minutes. The vegetables should be tender when pierced with a fork, with some crispy, caramelised edges. The sausages should be deeply browned and cooked through. (The corners of the peppers will look slightly charred, and the onions will appear sticky and translucent.)

Rest and garnish: Once done, remove the tray from the oven and let it rest for 5 minutes. This allows the juices to redistribute and the vegetables to settle. Sprinkle with fresh chopped parsley or basil just before serving. (The herbs add a bright, fresh note that cuts through the richness.)