Heat oven to 425˚F / 220˚C.
Place the capsicum / bell peppers, chili pepper, onion, tomato, garlic and thyme onto a baking sheet. Drizzle over the balsamic vinegar, 3 tablespoons olive oil, 1 teaspoon sea salt and lots of black pepper. Toss to combine until everything is well coated. Place into the oven and cook for 30 minutes.
Meanwhile, place the sausages onto the cutting board and drizzle with olive oil.
Carefully remove the baking sheet from the oven and give the peppers a toss. Nestle the sausages in and around the peppers, spreading them out evenly. Return to the oven until the capsicum (peppers) are completely soft and the sausages are golden on top.
Remove from the oven and season everything with sea salt and black pepper.
Serve with bread rolls, over polenta or tossed through pasta (it makes a really nice pasta salad, eaten cold for lunch the next day).